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Feb 98 Challenge

Volume Number: 14 (1998)
Issue Number: 2
Column Tag: Programmer's Challenge

Programmer's Challenge

by Bob Boonstra, Westford, MA

Image Decoder

This month's Challenge is much easier to state than it will be to implement. Your task this month is to write a decoder for Graphics Interchange Format images. GIF is a data stream-oriented file format used to define the transmission protocol of LZW-encoded bitmap data. Your code will read a file containing a GIF and draw the image in an offscreen graphics world. There are two versions of the GIF specification; this Challenge includes only the earlier and more common GIF87a format, not the GIF89a format. The format description is too long to include here, but you can find the GIF87a specification at: ftp://ftp.ncsa.uiuc.edu/misc/file.formats/graphics.formats/gif87a.doc

Other useful information on graphics formats in general is available at: http://www.cis.ohio-state.edu/hypertext/faq/usenet/graphics/fileformats-faq/top.html

The prototype for the code you should write is:

#include <QDOffscreen.h>
#include <stdio.h>
GWorldPtr ReadImage(FILE *inputFile);

The inputFile will have been opened for you in binary mode by the calling routine. ReadImage should read and parse the image, create a GWorld with the appropriate color table, draw the image in the GWorld, and return a GWorld pointer to the calling routine. The solution that correctly decodes a variety of images in the least amount of execution time will be the winner.

I thought for some time about the Compuserve / Unisys / LZW patent controverty before selecting this topic for the Challenge. The LZW algorithm used in GIF compression is patented by Unisys, and Unisys requires that any commercial software product that uses this algorithm, including software that reads GIF images, requires a license from Unisys. Freely distributed software does not require a license. Since the Challenge doesn't result in a software product, much less a commercial product, I decided to go ahead with this exploration of decoding efficiency.

This will be a native PowerPC Challenge, using the latest CodeWarrior environment. Solutions must be coded in C, C++, or Pascal. This Challenge was suggested by Peter Lewis, who earns 2 Challenge points for the suggestion.

Three Months Ago Winner

Congratulations to Jeff Mallett (Boulder Creek, CA) for submitting the winning entry to the Pente(tm) Challenge. The objective was to accumulate, in minimum execution time, the most points in a round-robin tournament of the board game Pente(tm). With only three entries, the tournament required only six games for each player to compete against each other player twice, once playing first and once playing second. Both the winning entry and the third-place entry by Randy Boring employed an alpha-beta search technique to find the best move, and both entries were successful in winning most of their games. Jeff's entry, however, was more efficient about pruning the search tree and therefore required significantly less execution time than Randy's entry. Since a point was deducted for each second of execution time, the winning entry lost significantly fewer points for inefficiency. In addition, the scoring algorithm in Jeff's AddStone routine takes advantage of all three methods of scoring points: captures, winning by placing 5 stones in a row, and leaving sequences of 4-in-a-row on the board at the conclusion of a game. His solution earned more points as a result, even though it won the same number of games as Randy's.

The table below lists the number of tournament wins, points earned, cumulative score, code size, data size, and programming language for each entry. The number in parentheses after the entrant's name is the total number of Challenge points earned in all Challenges to date prior to this one.

Name               Wins   Points   Score  Code  Data  Language
Jeff Mallett (74)    3      33     32.03  4872  7923    C
Sebastian Maurer     0      10      9.97  4860  208     C++
Randy Boring (66)    3      23   -374.90  7672  2649    C

Top 20 Contestants

Here are the Top Contestants for the Programmer's Challenge. The numbers below include points awarded over the 24 most recent contests, including points earned by this month's entrants. The scores have been adjusted to correct an error made in assigning points for the Stratego Challenge printed in the November issue.

Rank Name               Points
 1.  Munter, Ernst        200  
 2.  Boring, Randy         73
 3.  Cooper, Greg          61
 4.  Lewis, Peter          59
 5.  Mallett, Jeff         50
 6.  Nicolle, Ludovic      48
 7.  Murphy, ACC           34
 8.  Gregg, Xan            33
 9.  Antoniewicz, Andy     24
10.  Day, Mark             20
11.  Higgins, Charles      20
12.  Larsson, Gustav       20
13.  Studer, Thomas        20
14.  Gundrum, Eric         15
15.  Hart, Alan            14
16.  O'Connor, Turlough    14
17.  Picao, Miguel Cruz    14
18.  Saxton, Tom           12
19.  Cutts, Kevin          11
20.  8-way tie             10

There are three ways to earn points: (1) scoring in the top 5 of any Challenge, (2) being the first person to find a bug in a published winning solution or, (3) being the first person to suggest a Challenge that I use. The points you can win are:

1st place            20 points
2nd place            10 points
3rd place             7 points
4th place             4 points
5th place             2 points
finding bug           2 points
suggesting Challenge  2 points

Here is Jeff's winning solution:

MyPente.c
Copyright © 1997 Jeff Mallett
//
// Do a depth=1 search to sort moves. Then do a higher
// depth alpha-beta search to select the best move.
//
// Plays for score rather than to win. For example,
// doesn't try to win by getting 5 captures since
// there is no score incentive for this. It could be
// retuned to play for a win instead.

#include "Pente.h"

#define SEARCH_DEPTH 4
enum {
 _FRIEND = 0x0001,
 _ENEMY = 0x0002,
 _EMPTY = 0x0004,
 _WALL  = 0x0008
};

#define BORDER    1
#define BORDERS    2
#define INFINITY   32600
#define NA      0
#define MAX_CELLS   (31 + BORDERS) * (31 + BORDERS)

#define ESTIMATE_PLUS 1
#define WIN      2000
#define CAPTURE_SCORE 240
#define VULNERABLE   150

static short CHAIN_SCORE2[3][3] = {  //[color][open]
 { NA, NA, NA },
 { -1, -9, -2 },      // FRIEND
 { 1, 9, 2 }      // ENEMY
};
static short CHAIN_SCORE3[3][3] = {  //[color][open]
 { NA, NA, NA },
 { 3, 16, 40 },      // FRIEND
 { -2,-10,-30 }      // ENEMY
};
static short CHAIN_SCORE4[3][3] = {  //[color][open]
 {  NA, NA, NA },
 { 230, 240, 250 },  // FRIEND
 { -150,-155,-160 }  // ENEMY
};
static short CHAIN_SCORE5[3] = {    //[color]
 NA, WIN, -WIN
};
//                 1  2  3  4
static short BLOCK_SCORE[5] = { NA, 0, 14, 14, 22};
static short THREATS[] = {
 NA, NA,
 25, // 2: tria
 30, // 3: half-open four
 350, // 4: double trias
 370, // 5: tria + half-open four
 450, // 6: tessera or 2 half-open fours
 500, 500, 500, 500, 500, 500, 500, 500, 500, 500
};

static short gPreScore[MAX_CELLS], gEstimates[MAX_CELLS];
static short *gEstimatesStart, *gEstimatesEnd;
static short gBoard[MAX_CELLS], *gBoardStart, *gBoardEnd;
static short *gFirstStone, *gLastStone;
static short *gKillers[SEARCH_DEPTH], gPreviousThreats;
static short gDirections[8], *gDirectionsEnd;
static short gMoveNum, gScore, gStartDepth;
static short gBoardHalfSize, gSideLength, gBoardMax;
static short gCumCapturesFriend, gCumCapturesEnemy;
static short gAdjustment, gSE;

#define ADJUST(a)    ( (a) + gAdjustment )
#define TRANSLATE(x, y) \
 (gSideLength * ADJUST(y) + ADJUST(x))
#define GET_INDEX(p) ((p) - gBoard)
#define GET_X(i)   ( ((i) % gSideLength) - gAdjustment )
#define GET_Y(i)   ( ((i) / gSideLength) - gAdjustment )
#define UPDATE_ENDPOINTS(pSq, a, b) \
 if (pSq < a) a = pSq; \
 if (pSq > b) b = pSq

#define OPPONENT(side) (3 - (side))
#define OCCUPIED(x)   ((x) & (_FRIEND | _ENEMY))
#define EMPTY(x)    ((x) == _EMPTY)

// gChanges -- Array of unsigned longs containing data to
// undo moves
//   list of:
//     <pointer to position> <old position value>
//   terminated by a OL
static unsigned long gChanges[256], *gChangesEnd;
#define PUSH(x)    *(gChangesEnd++) = (x)
#define START_SAVE  PUSH(0L)
#define PUSH_SQ(pSq) \
  { PUSH((long)*(pSq)); PUSH((unsigned long)(pSq)); }
#define POP      *(--gChangesEnd)
#define TOP      *gChangesEnd

static short * ChooseNextMove();
static short AddStone(short alpha, short beta, short *pSq,
        short color, short depth,
        short capturesFriend, short capturesEnemy,
        short *firstStone, short *lastStone);
static long MyFindCaptures(Capture capture[], short *pSq,
        short us, short them);
static Boolean MyFindFive(short *pSq, short color);

InitPente
void InitPente(
 long boardHalfSize  /* e.g., 9 for a 19x19 board */
       /* all coordinates between -boardHalfSize
        and +boardHalfSize */
) {
 short i, j, *pSq;
 
 gBoardHalfSize = boardHalfSize;
 gSideLength = boardHalfSize * 2 + 1 + BORDERS;
 gSE = gSideLength + 1;
 gDirections[0] = -gSE;                // NW
 gDirections[1] = -gSideLength;        // N
 gDirections[2] = -gSideLength + 1;     // NE
 gDirections[3] = -1;                // W
 gDirections[4] = gSE;                // SE
 gDirections[5] = gSideLength;        // S
 gDirections[6] = gSideLength - 1;      // SW
 gDirections[7] = 1;                  // E
 gDirectionsEnd = &gDirections[8];
 
 gBoardMax = gSideLength * gSideLength;
 i = (gSideLength + 1) * BORDER;
 gBoardStart = &gBoard[i];
 gBoardEnd = &gBoard[gBoardMax - i];
 gEstimatesStart = &gEstimates[i];
 gEstimatesEnd = &gEstimates[gBoardMax - i];
 gFirstStone = gBoardEnd;
 gLastStone = gBoardStart;
 
 pSq = gBoard;
 do {
  *pSq = _WALL;
 } while (++pSq != gBoardStart);
 do {
  *pSq = _EMPTY;
 } while (++pSq != gBoardEnd);
 do {
  *pSq = _WALL;
 } while (++pSq < &gBoard[gBoardMax]);
 for (i = BORDER + boardHalfSize * 2 + 1;
    i<gBoardMax-gSideLength; i += gSideLength)
  for (j=0; j<BORDERS; ++j)
   gBoard[i+j] = _WALL;
 gCumCapturesFriend = gCumCapturesEnemy = gMoveNum = 0;
 gAdjustment = gBoardHalfSize + BORDER;
 gStartDepth = SEARCH_DEPTH - 1;
}

Pente
void Pente(
 Point opponentsMove,      /* your opponent moved here */
 Boolean playingFirst,      /* ignore opponentMove */
 Point *yourMove,          /* return your move here */
 Capture claimCaptures[],    /* return captured pairs here */
 long *numCaptures,       /* return # of claimCaptures */
 Boolean *claimVictory     /* return true if you claim
               victory with this move */
) {
 Point move;
 Capture opponentCaptures[8];
 
 short *pSq, *pNewSq, *d;
 short score, bestScore, i;
 short *pBestMove;
 
 *numCaptures = 0;
 *claimVictory = false;
 if (playingFirst) { // *** MOVE 1
  move.h = move.v = 0;
  pSq = &gBoard[TRANSLATE(0, 0)];
  *pSq = _FRIEND;
  UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
  *yourMove = move;
  gMoveNum = 1;
  return;
 }
 
 i = TRANSLATE(opponentsMove.h, opponentsMove.v);
 pSq = &gBoard[i];
 *pSq = _ENEMY;
 UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
 ++gMoveNum;

 if (gMoveNum == 1) { // *** MOVE 2
  move.h = move.v = -2;
  pSq = &gBoard[TRANSLATE(-2, -2)];
  *pSq = _FRIEND;
  UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
  *yourMove = move;
  gMoveNum = 2;
  return;
 }
 
 if (gMoveNum == 2) { // *** MOVE 3
  if (opponentsMove.v < opponentsMove.h) {
   if (opponentsMove.v < -opponentsMove.h) {
    // top triangle
    move.h = 0;
    move.v = 4;
   } else {
    // right triangle
    move.h = -4;
    move.v = 0;
   }
  } else {
   if (opponentsMove.v >= -opponentsMove.h) {
    // bottom triangle
    move.h = 0;
    move.v = -4;
   } else {
    // left triangle
    move.h = 4;
    move.v = 0;
   }
  }
  pSq = &gBoard[TRANSLATE(move.h, move.v)];
  *pSq = _FRIEND;
  UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
  *yourMove = move;
  gMoveNum = 3;
  return;
 }

 gChangesEnd = gChanges;
 gCumCapturesEnemy +=
   MyFindCaptures(opponentCaptures, &gBoard[i],
           _ENEMY, _FRIEND);
 for (pSq = gEstimatesStart; pSq != gEstimatesEnd; ++pSq)
  *pSq = 0;
 for (pSq = gFirstStone; pSq <= gLastStone; ++pSq)
  if (OCCUPIED(*pSq)) {
   d = gDirections;
   do {
    pNewSq = pSq + *d;
    if (EMPTY(*pNewSq)) {
     gEstimates[GET_INDEX(pNewSq)] += ESTIMATE_PLUS;
     pNewSq += *d;
     if (EMPTY(*pNewSq)) {
      gEstimates[GET_INDEX(pNewSq)] += ESTIMATE_PLUS;
     }
    }
   } while (++d != gDirectionsEnd);
  }

 for (pSq = gBoardStart; pSq != gBoardEnd; ++pSq)
  if (gEstimates[GET_INDEX(pSq)]) {
   i = GET_INDEX(pSq);
   gScore = gEstimates[i];
   gPreScore[i] = AddStone(-INFINITY, INFINITY, pSq,
            _FRIEND, 0, gCumCapturesFriend,
            gCumCapturesEnemy, gFirstStone,
            gLastStone);
  }

 for (i=0; i<SEARCH_DEPTH; ++i)
  gKillers[i] = NULL;
 bestScore = -INFINITY;
 pBestMove = NULL;
 pSq = ChooseNextMove();
 while (pSq) {
  i = GET_INDEX(pSq);
  gScore = gEstimates[i];
  score = AddStone(-INFINITY, -bestScore, pSq, _FRIEND,
       gStartDepth, gCumCapturesFriend,
       gCumCapturesEnemy, gFirstStone, gLastStone);
  gEstimates[i] = -1; // searched
  if (score > bestScore) {
   bestScore = score;
   pBestMove = pSq;
  }
  pSq = ChooseNextMove();
 }
  
 if (bestScore == -INFINITY) {
  for (pSq = gBoardStart; pSq != gBoardEnd; ++pSq)
   if (EMPTY(*pSq) && !gEstimates[GET_INDEX(pSq)]) {
    gScore = 0;
    score = AddStone(-INFINITY, -bestScore, pSq, _FRIEND,
                  gStartDepth, gCumCapturesFriend,
                  gCumCapturesEnemy, gFirstStone, gLastStone);
    if (score > bestScore) {
     bestScore = score;
     pBestMove = pSq;
    }
   }
  if (bestScore == -INFINITY) {
   DebugStr("\p no move found - Pente");
   return; //no move
  }
 }
 
 *pBestMove = _FRIEND;
 UPDATE_ENDPOINTS(pBestMove, gFirstStone, gLastStone);
 i = GET_INDEX(pBestMove);
 move.h = GET_X(i);
 move.v = GET_Y(i);
 *yourMove = move;
 ++gMoveNum;
 // find captures
 *numCaptures = MyFindCaptures(claimCaptures, pBestMove,
          _FRIEND, _ENEMY);
 gCumCapturesFriend += *numCaptures;
 if (gCumCapturesFriend >= 5) {
  *claimVictory = true;
 } else {
  *claimVictory = MyFindFive(pBestMove, _FRIEND);
 }
}

TermPente
void TermPente(void) { }

ChooseNextMove
short * ChooseNextMove()
{
 short i, *pSq;
 short *found = NULL;
 short high = -INFINITY;
 for (pSq = gBoardStart; pSq != gBoardEnd; ++pSq) {
  i = GET_INDEX(pSq);
  if (gEstimates[i] > 0 && gPreScore[i] > high) {
   found = pSq;
   high = gPreScore[i];
  }
 }
 return found;
}

AddStone
// Alpha-beta search routine
// returns score of how good it is for color
// alpha and beta apply for the opponent after the move
// is made
// gScore is absolute: + for _FRIEND
short AddStone(short alpha, short beta, short *pSq,
    short color, short depth, short capturesFriend,
    short capturesEnemy, short *firstStone,
    short *lastStone)
{
 register short *pNewSq, *d;
 short x, bestScore, t, *pEnd;
 short open, *killer;
 short threats, blocks, vulnerable;
 short opponent = OPPONENT(color);
 short saveScore = gScore;
  
 START_SAVE;
 threats = blocks = vulnerable = 0;
 d = gDirections;
 do {
  pNewSq = pSq + *d;
  
  if (*pNewSq == color) { // Next to friend
   if (d <= &gDirections[3]) {
    x = 1;
    open = 0;
    for (pNewSq += *d; *pNewSq == color; pNewSq += *d)
     ++x;
    if (EMPTY(*pNewSq))
     open = 1;
    for (pNewSq = pSq + *(d+4); *pNewSq == color;
       pNewSq += *(d+4))
     ++x;
    if (EMPTY(*pNewSq))
     ++open;
   } else {
    t = *(pSq + *(d-4));
    if (t == color)
     continue;
    x = 1;
    open = 0;
    if (EMPTY(t))
     open = 1;
    for (pNewSq += *d; *pNewSq == color; pNewSq += *d)
     ++x;
    if (EMPTY(*pNewSq))
     ++open;
   }
   
   switch (x) {
    case 1:  // 2-in-a-row
     gScore += CHAIN_SCORE2[color][open];
     if (open == 1)
      ++vulnerable;
     break;
    case 2:  // 3-in-a-row
     gScore += CHAIN_SCORE3[color][open];
     if (open == 2)
      threats += 2;        // tria = 2
     break;
    case 3:  // 4-in-a-row
     gScore += CHAIN_SCORE4[color][open];
     threats += open * 3;  // tessera = 6, half-open = 3
     break;
    default:  // 5-in-a-row (or more)
     gScore += CHAIN_SCORE5[color];
     threats = -99;        // game over
     break;
   }
   
  } else if (*pNewSq == opponent) {  // Next to enemy
   x = 1;
   for (pNewSq += *d; *pNewSq == opponent; pNewSq += *d)
    ++x;
    
   if (EMPTY(*pNewSq)) {
    blocks += BLOCK_SCORE[x];
   } else if (x == 2 && *pNewSq == color) {
    t = CAPTURE_SCORE;
    if (color != _FRIEND)
     t = -t;
    gScore += t;
    if (color == _FRIEND) {
     if (++capturesFriend >= 5) {
      threats = -99;  // game over
     }
    } else {  // color == _ENEMY
     if (++capturesEnemy >= 5) {
      threats = -99;  // game over
     }
    }
    if (depth) {
     pNewSq = pSq + *d;
     PUSH_SQ(pNewSq);
     *pNewSq = _EMPTY;
     pNewSq += *d;
     PUSH_SQ(pNewSq);
     *pNewSq = _EMPTY;
    }
   }
  }
 } while (++d != gDirectionsEnd);
  
 if (threats < 0) {
  // Game over
  bestScore = gScore;
  if (color != _FRIEND)
   bestScore = -bestScore;
  goto RESTORE;
 }
   
  // Not forced to make a bad move
 if (color == _FRIEND) {
  if (gScore < saveScore)
   gScore = saveScore;
 } else if (gScore > saveScore)
  gScore = saveScore;
 if (depth) {
  // Add stone
  PUSH_SQ(pSq);
  *pSq = color;
  UPDATE_ENDPOINTS(pSq, firstStone, lastStone);
  --depth; 
  gPreviousThreats = threats;
  bestScore = -INFINITY;
  // Killer move?
  killer = gKillers[depth];
  if (killer && EMPTY(*killer)) {
   saveScore = gScore;
    bestScore = AddStone(-beta, -alpha, killer,
           opponent, depth, capturesFriend,
           capturesEnemy, firstStone, lastStone);
   gScore = saveScore;
   if (bestScore > alpha) {
    if (bestScore >= beta) {
     bestScore = -bestScore;
     goto RESTORE;
    }
    alpha = bestScore;
   }
  }
  
  pEnd = lastStone + gSE;
  if (pEnd >= gBoardEnd)
   pEnd = gBoardEnd - 1;
  pSq = firstStone - gSE;
  if (pSq < gBoardStart)
   pSq = gBoardStart;
  do {
   if (EMPTY(*pSq) && pSq != killer) {
    d = gDirections;
    do {
     pNewSq = pSq + *d;
     if (OCCUPIED(*pNewSq) &&
        (*(pNewSq + *d) == *pNewSq ||
         *(pSq  - *d) == *pNewSq))
      break;
    } while (++d != gDirectionsEnd);
    if (d != gDirectionsEnd) {
     saveScore = gScore;
      t = AddStone(-beta, -alpha, pSq, opponent,
         depth, capturesFriend, capturesEnemy,
         firstStone, lastStone);
     gScore = saveScore;
     if (t > bestScore) {
      bestScore = t;
      if (t > alpha) {
       if (t >= beta) {
        gKillers[depth] = pSq;
        break;
       }
       if (depth >= gStartDepth-1)
        gKillers[depth] = pSq;
       alpha = t;
      }
     }
    }
   }
  } while (++pSq <= pEnd);
  if (bestScore == -INFINITY) {
   ++depth;
   goto TERMINAL;
  }
  bestScore = -bestScore;
  
 } else { // !depth
TERMINAL:
  bestScore = gScore;
  if (color != _FRIEND)
   bestScore = -bestScore;

  // Winning threats
  if (gPreviousThreats >= 5) {
   bestScore -= THREATS[gPreviousThreats];
  } else if (threats >= 5) {
   bestScore += THREATS[threats];
  } else if (gPreviousThreats == 4) {
   bestScore -= THREATS[gPreviousThreats];
  } else if (threats == 4) {
   bestScore += THREATS[threats];
  } else if (gPreviousThreats) {
   bestScore -= THREATS[gPreviousThreats];
  } else if (threats) {
   bestScore += THREATS[threats];
  }
  bestScore += blocks - vulnerable * VULNERABLE;
 }
 
RESTORE: 
 while (POP) {
  pSq = (short *)TOP;
  *pSq = POP;
 }
  
 return bestScore;
}

MyFindCaptures
long MyFindCaptures(Capture capture[], short *pSq,
          short us, short them)
{
 short i, *p1, *p2;
 short myCaptures = 0;
 short *d = gDirections;
 
 do {
  p1 = pSq + *d;
  if (*p1 == them) {
   p2 = p1 + *d;
   if (*p2 == them && *(p2 + *d) == us) {
    *p1 = *p2 = _EMPTY;
    i = GET_INDEX(p1);
    capture[myCaptures].stone1.h = GET_X(i);
    capture[myCaptures].stone1.v = GET_Y(i);
    i = GET_INDEX(p2);
    capture[myCaptures].stone2.h = GET_X(i);
    capture[myCaptures].stone2.v = GET_Y(i);
    ++myCaptures;
   }
  }
 } while (++d != gDirectionsEnd);
 return myCaptures;
}

MyFindFive
Boolean MyFindFive(short *pSq, short color)
{
 short x, *d, *pNewSq, i;
 
 d = gDirections;
 i = 0;
 do {
  x = 1;
  for (pNewSq = pSq + *d; *pNewSq == color; pNewSq += *d)
   ++x;
  for (pNewSq = pSq + *(d+4); *pNewSq == color;
     pNewSq += *(d+4))
   ++x;
  if (x >= 5)
   return true;
  ++d;
 } while (++i < 4);
 return false;
}
 

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Together helps you organize your Mac, giving you the ability to store, edit and preview your files in a single clean, uncluttered interface. Features Smart storage. With simple drag-and-drop... Read more
Apple MainStage 3.3 - Live performance t...
Apple MainStage makes it easy to bring to the stage all the same instruments and effects that you love in your recording. Everything from the Sound Library and Smart Controls you're familiar with... Read more
Apple iOS 10.3 - The latest version of A...
iOS 10 is the biggest release of iOS ever. A massive update to Messages brings the power of the App Store to your conversations and makes messaging more personal than ever. Find your route with... Read more
Postbox 5.0.12 - Powerful and flexible e...
Postbox is a new email application that helps you organize your work life and get stuff done. It has all the elegance and simplicity of Apple Mail, but with more power and flexibility to manage even... Read more
Apple Keynote 7.1 - Apple's present...
Easily create gorgeous presentations with the all-new Keynote, featuring powerful yet easy-to-use tools and dazzling effects that will make you a very hard act to follow. The Theme Chooser lets you... Read more
Apple Pages 6.1 - Apple's word proc...
Apple Pages is a powerful word processor that gives you everything you need to create documents that look beautiful. And read beautifully. It lets you work seamlessly between Mac and iOS devices, and... Read more
Apple Numbers 4.1 - Apple's spreads...
With Apple Numbers, sophisticated spreadsheets are just the start. The whole sheet is your canvas. Just add dramatic interactive charts, tables, and images that paint a revealing picture of your data... Read more

The best deals on the App Store this wee...
Deals, deals, deals. We're all about a good bargain here on 148Apps, and luckily this was another fine week in App Store discounts. There's a big board game sale happening right now, and a few fine indies are still discounted through the weekend.... | Read more »
The best new games we played this week
It's been quite the week, but now that all of that business is out of the way, it's time to hunker down with some of the excellent games that were released over the past few days. There's a fair few to help you relax in your down time or if you're... | Read more »
Orphan Black: The Game (Games)
Orphan Black: The Game 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: Dive into a dark and twisted puzzle-adventure that retells the pivotal events of Orphan Black. | Read more »
The Elder Scrolls: Legends is now availa...
| Read more »
Ticket to Earth beginner's guide: H...
Robot Circus launched Ticket to Earth as part of the App Store's indie games event last week. If you're not quite digging the space operatics Mass Effect: Andromeda is serving up, you'll be pleased to know that there's a surprising alternative on... | Read more »
Leap to victory in Nexx Studios new plat...
You’re always a hop, skip, and a jump away from a fiery death in Temple Jump, a new platformer-cum-endless runner from Nexx Studio. It’s out now on both iOS and Android if you’re an adventurer seeking treasure in a crumbling, pixel-laden temple. | Read more »
Failbetter Games details changes coming...
Sunless Sea, Failbetter Games' dark and gloomy sea explorer, sets sail for the iPad tomorrow. Ahead of the game's launch, Failbetter took to Twitter to discuss what will be different in the mobile version of the game. Many of the changes make... | Read more »
Splish, splash! The Pokémon GO Water Fes...
Niantic is back with a new festival for dedicated Pokémon GO collectors. The Water Festival officially kicks off today at 1 P.M. PDT and runs through March 29. Magikarp, Squirtle, Totodile, and their assorted evolved forms will be appearing at... | Read more »
Death Road to Canada (Games)
Death Road to Canada 1.0 Device: iOS Universal Category: Games Price: $7.99, Version: 1.0 (iTunes) Description: Get it now at the low launch price! Price will go up a dollar every major update. Update news at the bottom of this... | Read more »
Bean's Quest Beginner's Guide:...
Bean's Quest is a new take on both the classic platformer and the endless runner, and it's free on the App Store for the time being. Instead of running constantly, you can't stop jumping. That adds a surprising new level of challenge to the game... | Read more »

Price Scanner via MacPrices.net

13-inch MacBook Airs, Apple refurbished, in s...
Apple has Certified Refurbished 2016 13″ MacBook Airs available starting at $849. An Apple one-year warranty is included with each MacBook, and shipping is free: - 13″ 1.6GHz/8GB/128GB MacBook Air: $... Read more
12-inch Retina MacBooks on sale for $1199, sa...
B&H has 12″ 1.1GHz Retina MacBooks on sale for $100 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 12″ 1.1GHz Space Gray Retina MacBook: $1199 $100 off MSRP - 12″ 1.1GHz... Read more
Save up to $260 with Apple refurbished 12-inc...
Apple has Certified Refurbished 2016 12″ Retina MacBooks available for $200-$260 off MSRP. Apple will include a standard one-year warranty with each MacBook, and shipping is free. The following... Read more
13-inch 2.7GHz Retina MacBook Pro on sale for...
B&H Photo has the 2015 13″ 2.7GHz/128GB Retina Apple MacBook Pro on sale for $170 off MSRP. Shipping is free, and B&H charges NY tax only: - 13″ 2.7GHz/128GB Retina MacBook Pro (MF839LL/A): $... Read more
15-inch 2.2GHz Retina MacBook Pro on sale for...
B&H Photo has the 2015 15″ 2.2GHz Retina MacBook Pro (MJLQ2LL/A) on sale for $1799.99 including free shipping plus NY sales tax only. Their price is $200 off MSRP. Read more
Save up to $160 with Apple refurbished 9-inch...
Apple has Certified Refurbished 9″ and 12″ Apple iPad Pros available for up to $160 off the cost of new iPads. An Apple one-year warranty is included with each model, and shipping is free: - 32GB 9″... Read more
Apple Chip Foundry TSMC To Begin A11 System-o...
Digitimes’ Steve Shen is reporting today that according to the Chinese-language Economic Daily News (EDN), chipmaker and major Apple supplier foundery Taiwan Semiconductor Manufacturing Company (TSMC... Read more
MacX MediaTrans 3.5 iOS Data Transfer Spring...
MacXDVD Software has announced general availability of the latest MacX MedTrans 3.5, featuring a new user interface (UI). MacX MediaTrans is ann iPhone manager that enables free data transfer between... Read more
Regular Price $19.95 DupeZap 4 Finder For OS...
Hyperbolic Software has announced the release of DupeZap 4.0.2, their modern duplicate finder developed exclusively for macOS. DupeZap 4 is an utility for Mac owners seeking to reclaim disk space... Read more
B-Eng Releases SSD Health Check for MVNe for...
Fehraltorf, Switzerland based B-Eng has announced the release and immediate availability of SSD Health Check for MVNe for MacBook Pro, their app that delivers important data and insights for MVNe... Read more

Jobs Board

Fulltime aan de slag als shopmanager in een h...
Ben jij helemaal gek van Apple -producten en vind je het helemaal super om fulltime shopmanager te zijn in een jonge en hippe elektronicazaak? Wil jij werken in Read more
*Apple* Mobile Master - Best Buy (United Sta...
**492889BR** **Job Title:** Apple Mobile Master **Location Number:** 000886-Norwalk-Store **Job Description:** **What does a Best Buy Apple Mobile Master do?** Read more
*Apple* Mobile Master - Best Buy (United Sta...
**492472BR** **Job Title:** Apple Mobile Master **Location Number:** 000470-Seattle-Store **Job Description:** **What does a Best Buy Apple Mobile Master do?** Read more
*Apple* Mobile Master - Best Buy (United Sta...
**492562BR** **Job Title:** Apple Mobile Master **Location Number:** 000853-Jackson-Store **Job Description:** **What does a Best Buy Apple Mobile Master do?** Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
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