Spellstack: Word Sort Puzzle

Spellstack is a word sort puzzle for Android. Pour letters between tubes until every tube spells a real word. It plays like water sort or ball sort, but tubes hold letters instead of colors. A stack only locks when it spells one of the target words, read from bottom to top. Short 3-letter puzzles fit a coffee break; overlapping 4- and 5-letter words are there when you want a tougher brain teaser. How to play • Tap a tube to pick its top letter • Tap another tube to pour • Letters read bottom to top • A gold glow means that word is locked • Undo and restart are always free • Peek or a pour hint costs coins, or watch an optional short ad Play your way • 500 campaign puzzles across 8 worlds • Daily word puzzle and streak • 60-second Blitz • Stars, chests, XP, and ranks • Offline word game — no account and no sign-in Spellstack is a casual letter-sort puzzle for a mixed audience 13 and older. It is family-friendly and not directed at children under 13. Ads are optional rewarded hints, occasional ads after campaign clears, and an app-open ad after five levels. A one-time purchase in Settings removes ads for that Google account. FAQ What is Spellstack? An Android word puzzle where you pour letters in tubes to spell words. Is Spellstack like water sort? Yes. The pour-and-stack feel is the same as water sort and ball sort. The difference is that a tube locks only when it spells a real word. Does Spellstack work offline? Yes. The campaign, Daily puzzle, Blitz, and dictionary run on your phone. The internet is used only for ads and privacy choices. Who is Spellstack for? A mixed audience 13 and older. Family-friendly, not directed at children under 13. Is there a Spellstack account? No. Progress stays on the device. Can I remove ads? Yes. Remove ads is a one-time purchase in Settings, tied to your Google account. Restore purchases puts it back after a reinstall.