Conto: Number Logic Puzzle

The café bill is wrong. A few things nobody ordered crept onto it, and the totals at the end of every row and under every column are all you have to go on. Cross out the extras until what is left in every line adds up. Each line you get right is stamped PAID with a ring of the till; get them all and the whole bill is PAID IN FULL.

TAP, CROSS, CIRCLE
Tap a price to cross it out, tap again to circle it as a keeper, tap once more to clear it. Under every total is what your circled prices add up to so far, so you always know how far off you are, and it turns red the moment the line can no longer make its total. Every mark is yours: Clear wipes the bill in one step you can undo, and Auto finish waits in Settings for anyone who wants it.

ONE ANSWER, NO GUESSING
Every bill has exactly one answer, and every one can be settled by reasoning alone. Each is proven twice before it is dealt: once worked out line by line the way you would, and once by counting every possible answer. Stuck? A hint fixes your first wrong mark, or proves the next price and lights the line that proves it, and its gold mark stays put.

ONE SHARED BILL A DAY
A new daily bill every day, the same for every player. Settle it to keep your streak, then take on the Daily Master, a bigger bill with refunds. Share your result card with friends: your two times, your hints and your streak, and never a spoiler.

FOUR COURSES, ENDLESS BILLS
Espresso is a quick four by four. Lunch is five by five. Dinner is six by six, where the lines start to lean on each other. Banquet is seven by seven with refunds: red negative prices that raise what is left when you cross them out. Settle ten bills on one course and the next one opens. Bills are generated, not hand made, so there is always another, and bill 12 on your phone is bill 12 on every phone.

TEN SPECIAL SHOPS
A Christmas market, a candy shop, a royal banquet, a ski chalet, a museum gift shop, a snack stand under the big top and a saloon out west, each with 32 bills from Espresso to the nine by nine Gala. Three extreme shops deal Gala bills only, prices up to 19 and as many as eleven refunds a bill: a Venetian café, the codebreakers' ledger and the harbour fish market.

CALM BY DESIGN
No clock on screen, no lives, no failing: a bill stays open until you settle it, and one left half settled is saved just as you left it. Undo and redo every mark. Terracotta tiles, a thermal receipt with torn edges, a navy pen and a green stamp, with music, sounds and haptics you can switch off.

Plays offline, portrait, one hand, sixteen languages.

Conto is free, funded by a full screen ad between some bills. Optional extras stay optional: ten special shops and hint bundles, plus a free hint for every two short ads you choose to watch. You start with three hints, and no bill ever needs one. No subscription, and no account to create.

Recent changes:
New: remove the ads. Subscribe monthly or yearly from the store and the ads between games are gone, while the videos you choose to watch for a reward stay. Plus minor improvements and fixes.