{"id":7816,"date":"2026-04-20T23:13:25","date_gmt":"2026-04-20T23:13:25","guid":{"rendered":"https:\/\/robertjwallace.com\/?p=7816"},"modified":"2026-04-20T23:18:15","modified_gmt":"2026-04-20T23:18:15","slug":"showcard-a-card-reveal-tool-for-performers","status":"publish","type":"post","link":"https:\/\/robertjwallace.com\/es\/showcard-a-card-reveal-tool-for-performers\/","title":{"rendered":"ShowCard \u2014 A Card Reveal Tool for Performers"},"content":{"rendered":"

\u2663 \u2665 \u2660 \u2666<\/p>\n\n\n\n

What is ShowCard?<\/h2>\n\n\n\n

ShowCard is a mobile web app designed for card performers. It lets you silently encode a playing card into your phone using natural-looking gestures, then reveal it dramatically at the right moment.<\/p>\n\n\n\n

The encoding happens in two steps as you handle the phone. First, the suit is registered by where your thumb lands as you pick up the phone. Then a second touch encodes the value. Neither touch looks deliberate to an observer \u2014 they’re the natural contacts of someone checking their phone.<\/p>\n\n\n\n

When you’re ready for the reveal, either lift the phone or give it a subtle motion and the card fades into view. The whole sequence, from encoding to reveal, can be made to look completely incidental.<\/p>\n\n\n\n\n\n\n\n

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Installing ShowCard<\/h2>\n\n\n\n

ShowCard is a Progressive Web App (PWA). There is nothing to download from an app store \u2014 you install it directly from the browser. Once installed it works completely offline, launches full-screen from your home screen, and behaves like a native app.<\/p>\n\n\n\n

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Important:<\/strong> You must use the correct browser for installation. Firefox does not support PWA installation. Use Safari on iPhone<\/strong> y Chrome on Android<\/strong>.<\/p>\n<\/blockquote>\n\n\n\n

iPhone \u2014 Safari<\/h3>\n\n\n\n
    \n
  1. Open Safari and go to robertjwallace.com\/showcard<\/a><\/code><\/li>\n\n\n\n
  2. Tap the Compartir<\/strong> button (box with arrow pointing up)<\/li>\n\n\n\n
  3. Scroll down and tap Add to Home Screen<\/strong><\/li>\n\n\n\n
  4. Tap Add<\/strong> in the top right<\/li>\n<\/ol>\n\n\n\n

    Android \u2014 Chrome<\/h3>\n\n\n\n
      \n
    1. Open Chrome and go to robertjwallace.com\/showcard<\/a><\/code><\/li>\n\n\n\n
    2. Tap the three-dot menu<\/strong> in the top right<\/li>\n\n\n\n
    3. Tap Add to Home Screen<\/strong><\/li>\n\n\n\n
    4. Tap Add<\/strong> to confirm<\/li>\n<\/ol>\n\n\n\n

      After installation, tap the ShowCard icon on your home screen. It will open full-screen with no browser chrome. The app caches all card images on the first load, so it will work with no internet connection from that point on.<\/p>\n\n\n\n

      \n

      iPhone note:<\/strong> The first time you launch, iOS will ask for permission to access motion and orientation sensors. Allow this \u2014 it is required for the pickup trigger to work.<\/p>\n<\/blockquote>\n\n\n\n

      \n\n\n\n

      How to Use ShowCard<\/h2>\n\n\n\n

      When the app opens it shows a blank screen:
      <\/p>\n\n\n\n

      \"\"<\/figure>\n\n\n\n

      The Encoding Grid<\/h3>\n\n\n\n

      The phone screen is invisibly divided into zones. You never need to look at them \u2014 after a little practice the positions become muscle memory.<\/p>\n\n\n\n

      Suit \u2014 4 horizontal rows, top to bottom:<\/strong><\/p>\n\n\n\n

      Zone<\/th>Suit<\/th><\/tr><\/thead>
      Top quarter<\/td>\u2663 Clubs<\/td><\/tr>
      Upper middle<\/td>\u2665 Hearts<\/td><\/tr>
      Lower middle<\/td>\u2660 Spades<\/td><\/tr>
      Bottom quarter<\/td>\u2666 Diamonds<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

      Value \u2014 3\u00d74 grid, reading left to right, top to bottom:<\/strong><\/p>\n\n\n\n

      <\/th>Left<\/th>Centre<\/th>Right<\/th><\/tr><\/thead>
      Top row<\/strong><\/td>A<\/td>2<\/td>3<\/td><\/tr>
      Second row<\/strong><\/td>4<\/td>5<\/td>6<\/td><\/tr>
      Third row<\/strong><\/td>7<\/td>8<\/td>9<\/td><\/tr>
      Bottom row<\/strong><\/td>10<\/td>J<\/td>Q<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

      The King is a special case \u2014 see below.<\/p>\n\n\n\n

      The Sequence<\/h3>\n\n\n\n

      1. Phone face down on the table.<\/strong>
      The app is waiting. Nothing is visible.<\/p>\n\n\n\n

      2. Pick up the phone.<\/strong>
      As it turns face up, your thumb naturally contacts the screen. The vertical position of that first touch encodes the suit. If the suit display is enabled, the suit symbol appears large on screen.<\/p>\n\n\n\n

      3. Touch the screen a second time.<\/strong>
      The position within the 3\u00d74 grid encodes the card value. The image is silently pre-loaded.<\/p>\n\n\n\n

      4. Trigger the reveal.<\/strong>
      Either lift or move the phone (motion trigger) or tap the screen a third time (tap trigger \u2014 see Settings). After the reveal delay, the card fades dramatically into view.<\/p>\n\n\n\n

      5. Reset.<\/strong>
      Tap the screen to return to idle (if tap-to-reset is enabled), or open and close Settings.<\/p>\n\n\n\n

      The King<\/h3>\n\n\n\n

      Because the 3\u00d74 grid only has 12 cells (Ace through Queen), the King is encoded differently. With the suit locked and before touching for a value, give the phone a quick shake \u2014 three sharp jolts. The King is loaded silently and the next trigger will reveal it.<\/p>\n\n\n\n

      The King can be disabled entirely in Settings if you don’t need it.<\/p>\n\n\n\n

      \n\n\n\n

      Settings<\/h2>\n\n\n\n

      Open Settings by tapping the invisible target in the top-right corner<\/strong> of the screen. On Android you can also use the volume up button<\/strong> if using the native app.<\/p>\n\n\n\n

      \"\"<\/figure>\n\n\n\n
      Setting<\/th>What it does<\/th><\/tr><\/thead>
      King card<\/strong><\/td>Enables or disables King encoding via shake. Turn off if your routine only uses Ace through Queen.<\/td><\/tr>
      Show suit<\/strong><\/td>When on, the suit symbol is displayed after the first touch. When off, the suit is encoded silently with nothing shown on screen.<\/td><\/tr>
      Tap to reset<\/strong><\/td>When on, touching the screen after the card is shown resets the app. When off, nothing happens on touch \u2014 open and close Settings to reset. Useful when you want the card to stay on screen without accidental resets.<\/td><\/tr>
      Tap to reveal<\/strong><\/td>When off (default), picking up or moving the phone reveals the card. When on, a third touch triggers the reveal. Recommended for iPhone, or any situation where motion triggering is unreliable.<\/td><\/tr>
      Reveal delay<\/strong><\/td>How long after the trigger before the card starts to appear. Range: 0.5 to 10 seconds.<\/td><\/tr>
      Fade duration<\/strong><\/td>How long the fade-in animation takes. Range: 1 to 5 seconds.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

      All settings are saved automatically and persist across sessions.<\/p>\n\n\n\n

      \"\"
      Suit display if toggled on<\/figcaption><\/figure>\n\n\n\n
      \"\"
      Card display<\/figcaption><\/figure>\n\n\n\n
      \n\n\n\n

      Tips<\/h2>\n\n\n\n