---
title: Puzzle Games Like Sudoku and Nonograms: Try Thermometers
description: If you enjoy Sudoku or nonograms, Thermometers is a logic puzzle to try next. What carries over, what is new, and where to play it free on iPhone and iPad.
url: https://www.arbazsiddiqui.me/app/mercuro/games-like-sudoku-and-nonograms/
---

# Like Sudoku or nonograms? Try Thermometers

The one-answer logic of Sudoku, the edge counts of nonograms, and a twist all its own. Mercury has to rise from the bulb.

App Store: https://apps.apple.com/app/id6762402072

## The Sudoku part

A well-made Sudoku has a single solution ([Wikipedia: Sudoku](https://en.wikipedia.org/wiki/Sudoku)), and you reach it by ruling things out, never by guessing. Thermometers runs on the same promise. Every Mercuro board has exactly one answer, and every cell can be worked out from the clues.

There are no digits to place. Each cell is filled or empty, so the logic is about counting and order instead of which number goes where.

## The nonogram part

Nonograms put numbers on the edges of the grid and ask you to fill cells or leave them blank ([Wikipedia: Nonogram](https://en.wikipedia.org/wiki/Nonogram)). So does Thermometers. The difference is what the numbers mean. A nonogram clue lists runs of filled cells; a Thermometers clue is a plain count, and the thermometer shapes do the rest.

## The new part

The glass adds order. Mercury starts at the bulb and rises without gaps, so a filled cell means every cell back to the bulb is filled too, and an empty cell means everything beyond it is empty. Most of the solving is playing those two facts against the counts.

See the [rules and a worked example](https://www.arbazsiddiqui.me/app/mercuro/how-to-play-thermometers/).

## Start on 5x5

Mercuro has 330 free puzzles on eight board sizes, so you can start small on 5x5 and climb to 12x12 when you are ready. Three new dailies land on top every day. It is free on iPhone and iPad.

## Questions

**Do I need to do any maths?** Only counting. No number is ever bigger than the length of a row.

**Is there a picture at the end, like a nonogram?** No. The reward is the solved board, not a hidden image.

**Where can I play Thermometers?** Mercuro, on iPhone and iPad, is free with 330 puzzles and three new ones a day.