Comparison

Blue Switch vs Sudoku Hint

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Blue Switch

Control 2, 4, or 8 channel Bluetooth BLE relay modules from your iPhone or iPad. Assign custom names to modules and individual relays for easy identification and management. Enhance security by changing the default password.

Highlights
  • Control 2, 4, or 8 channel relay modules
  • Bluetooth BLE connectivity
  • Assign custom module aliases
  • Assign custom relay aliases
  • Change default password for security
  • Connect to multiple modules
Features
Read full description

This app allows you to control a 2, 4 or 8 Channel Relay Module Bluetooth BLE with your iPhone or iPad. To use this app, you need one of these three modules: "2 Channel Relay Module Bluetooth BLE" "4 Channel Relay Module Bluetooth BLE" "8 Channel Relay Module Bluetooth BLE" These modules can be ordered at many online shops. Please use a search engine to find a shop. This app can be connected with any number of modules. By entering an alias, the modules are marked clearly and can easily be assigned to a use area. Name the modules for example "Relay 1", "Relay 2", "Electronic lab project" or "Ambient Light". An alias can also be entered for each relay. The default password for these modules is usually "12345678". For more security, the app also allows you to change the password. The password must be eight digits long.

About

Sudoku Hint

Features
Read full description

Need help with a Sudoku puzzle on paper? Sudoku Hint is a simple AI-powered Sudoku solver, hint tool and mistake checker that works directly from a photo. Take a picture of your paper Sudoku and get one clear hint at a time — without revealing the entire solution. Unlike a traditional Sudoku solver where you have to enter the whole grid manually, Sudoku Hint uses your camera and AI to read the puzzle for you. It is designed to recognize both printed and handwritten Sudoku numbers. USE SUDOKU HINT TO: • Get a Sudoku hint when you are stuck • Check your Sudoku for mistakes • Find an incorrect handwritten number and see the correct value • Scan a paper Sudoku with your camera instead of typing in the grid • Get another hint from the same Sudoku photo • Use “Only look for errors” when you want to solve the rest yourself MADE FOR PAPER SUDOKU Sudoku Hint is especially useful if you enjoy newspaper, magazine or printed Sudoku puzzles. Simply photograph the complete 9×9 Sudoku grid and let the app analyze it. The app distinguishes between the original printed clues and numbers you have written in yourself. This makes it useful both as a Sudoku checker and as a source of hints when you need help with the next move. ONE HINT AT A TIME Sudoku Hint does not immediately show you the completed puzzle. Instead, it gives you one useful Sudoku clue at a time, so you can continue solving the puzzle yourself. If you only want to know whether you have made a mistake, enable “Only look for errors”. SIMPLE AND AD-FREE No ads. No account required. Just take a photo and ask for help. Sudoku Hint includes 3 free hints so you can try it before buying anything. Additional hints can be purchased inside the app. Sudoku Hint uses AI image recognition, which can occasionally misread a number. Always check the photographed grid and use your own judgement when following a hint.

Screenshots

Blue Switch4 screens
Sudoku Hint4 screens

Verdict

The call

The clearest difference is ads: Sudoku Hint at none against Blue Switch's shown. Sudoku Hint also leads on update cadence (every 3 weeks vs every 3 months) and iOS requirement (15.1 vs 18.0). On price, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Blue Switch sells 1 one-off in-app purchase and Sudoku Hint sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Blue Switch ships an update every 3 months, Sudoku Hint every 3 weeks. The most recent releases landed on October 23, 2026 and October 22, 2026 respectively.

Scorecard3 real differences · 7 level
Blue Switch versus Sudoku Hint: the parameters behind the verdict, then further details
ParameterBlue SwitchSudoku Hint
PriceFreeFree
Rating3.8 (43 ratings) — better—
Positive reviews16.7% of reviews—
Number of ratings43 — better—
Update frequencyEvery 3 monthsEvery 3 weeks — better
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPadiPhone, iPod
Requires iOS18.015.1 — better
Further details — not scored
Size39 MB31 MB
Age rating4+4+
DeveloperVitalij SchaeferLeif Lauridsen

In-app purchases

1 purchases

Blue Switch

One-time1
  • Remove Ads$17.99
1 purchases

Sudoku Hint

One-time1
  • 100 Hints$1.99

Questions

Is Blue Switch free?
Blue Switch is free to download, with in-app purchases available.
Is Sudoku Hint free?
Sudoku Hint is free to download, with in-app purchases available.
Do Blue Switch or Sudoku Hint have ads?
Blue Switch shows ads; Sudoku Hint does not.
Which is updated more often, Blue Switch or Sudoku Hint?
Blue Switch ships an update every 3 months, and Sudoku Hint every 3 weeks. Most recently, Blue Switch was updated on October 23, 2026 and Sudoku Hint on October 22, 2026.

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