Sven's SudokuPad
Reviews and Complaints

It is a great companion app for Cracking the Cryptic fans. However, compare to Cracking the Cryptic app, Mac support fo this app is dismal. I can't even use keypad to enter numbers. Cracking the Cryptic app (written by the same person) at least has some support for Mac but this one needs the same level of care.

This continues to be, by far, my favorite method for solving sudokus. The newer features of the web version (e.g., letter tool, enhanced pen features, killer cage calculator) make it even better and I wish some of these made it to the iOS version as well.

Finally get to save the YT puzzles all in one place. The features are basic, so it does not have cloud saves or ways to categorize the puzzles. It does not stop the clock when the app is out of focus.

However, there are some bugs that are really annoying to deal with:
- Scalability: Once there are 100+ puzzles, the app becomes really slow (10+ seconds delay) when going back to the puzzle listing.
- Sorting: The sort order seems to have issues. The date sort can return incorrect results, making it a bit hard to find the latest puzzle that I am working on
- Saving: Sometimes, exiting the puzzle (by pressing the back button) does not save the progress. There is this one puzzle that I have “finished" multiple times and the results are not saved. There is also this one puzzle that is marked as completed but when you select it, it claims it is not completed.

Downloaded the app as a way of supporting Sven and the CtC channel since I can't afford a Patreon commitment or anything else.

The app itself is obviously great, and as others have said, it's pretty much the best interface I've come across for solving sudokus.

I wish the feature to input your own puzzles allowed for variations like arrows, killer cages, etc since those things are supported by the app (whenever you import a puzzle from CtC, it has all those features).

I'm someone who is interested in learning to set puzzles, and I would love it if this app were my tool for doing so.

(Also, pen tool plz. >.

This is a wonderful app to solve the puzzles featured on the channel, however, there's some key features in the web app that are missing from this. Notably, the letter function, the extra colors, diagonal lines on the line tool, and the new fog of war mechanic are missing. The latter is, albeit, quite new, but seeing as this hasn't been updated in 11 months, adding at least some of the new things would be great. Additionally, the ability to detect if a solution is correct for irregular or otherwise "non-normal" sudoku puzzles would be most welcome. When I do complete one of those, it is often marked as wrong and therefore incomplete, so I usually just delete it from the app.

Overall though, it works superbly well for almost every puzzle!

There's no question that Sven's app is the best Sudoku app available to download. But unfortunately it's not the best Sudoku app available. That would be Sven's web version of the app. Over the past year, that app has consistently received more and more improvements, enhancements, and features, while those of us who downloaded the iOS version have been left behind. It's gotten to the point where I no longer even bother opening the app any longer to play CTC puzzles, because playing on the web is such a better experience.

When using the CtC web site to solve puzzles you can add pencil marks and when you solved a number the pencil marks associated with that number in the same columns and rows would disappear. Missing that in this app. Wish it was their. I tend to make mistakes because of pencil marked numbers left behind.

I've had a lot of fun using this app, it makes solving sudokus much easier. However the web version still has more features that I hope will be implemented like being able to use letters, and cage sums calculators etc. Also please add more colors!

Strengths: This is easily the best way to solve a Sudoku puzzle whether it is one from CtC or one from another source. I had been hoping for something like it since I first used the CtC web app for the videos. Very easy to use and makes me want to solve more puzzles again after putting them down a few months ago.

Areas for improvement: It would be very helpful if it had the ability to use the phone camera to autodetect a puzzle that is on paper instead of having to manually enter each number in a custom puzzle. It would also help if the timer automatically paused if switching to another app or turning off the phone.

I was excited about this app, and liked the different notations available and the fact that you can add other sudokus to use the app's functionalities to solve them. The main problem I had with it, which for me is a big one, is the fact that it did not save the progress I made in the sudoku. Short pauses were ok, but when I left a puzzle to continue the following day, I had to start from scratch. It had not saved neither the pencil markings nor the numbers I had found.

Best app for solving puzzles entered from any source manually (or via a link for CtC puzzles).

Loses at least a star for updates deleting all saved puzzles and all progress made on the puzzles bundled with the app. This is a huge bummer. Be prepared to lose everything or never update.

Would be great if the dev used iCloud to save puzzles and be able to pick up progress on another device.

This is a great app for solving the Cracking the Cryptic hand-crafted puzzles featured on the YT channel, as well as any other Sudoku puzzle that you care to enter manually. Puzzles are stored locally, offline, and completion times are stored, so you can build up a nice library of puzzles, abandon a puzzle and pick up where you left off weeks or months later, and compete against your best times.

However, this iOS app has fallen far behind the web app in features, and some of the puzzles featured on the CtC YT channel are much harder to solve in this app as a result. Unfortunately, the web app does not scale nicely to mobile touch interfaces and provides no mechanism for storing puzzles.

This app needs an update.

It gets 5 stars for being the only app of its kind on iOS to allow solving puzzles from all over the internet. Previously, I had a huge bookmark folder of puzzles I had to wait until I was on a desktop to solve, but now I can solve them on my phone, and that is a beautiful thing.

Some suggestions: The process of cleaning up pencilmarks can be rather tedious, so auto-pencilmark elimination in row/column when placing digits would be a very nice feature to have as something that could be enabled in settings.

Also, while long pressing on a cell highlight similar cells, it would be nice to be able to do this highlighting from the number pad with a long press. For example, if I wanted to highlight all cells with corner marked 5s, I could go to corner marks and hold the 5 button to do so. Currently, I have to have a corner marked 5 with no other corner marks to highlight just the 5s.

Some sort of cloud syncing would also be nice so people could continue playing puzzles on different devices. Those features missing aside, this is still the best iOS app for solving sudokus and has earned all 5 of these stars until that stops being true.

Edit: also auto-pausing the clock when switching apps would be good. There is some glitchy behavior with the clock in general, but I am not personally reliant on it.

I love the app. Since finding CtC I have been spoiled with solving Sudoku with their web browser app. This doesn't have all the functionality (ability for non classic sudoku) much to many peoples chagrin, but it will soon. Even without it I'm loving it. I'm finally getting through my World of Sudoku book by Akash Doulani now that I have an app (that I like) to solve them in. I'm no good with pencil and the other puzzle site is not to my liking. Everyone should buy it just to put in classic puzzles from sudoku books.

The tools from cracking the cryptic are definitely available here. That is awesome. I would love to see two updates though.
First I would love to see the ability to change the font-size of the corner pencil-marks. In my opinion being able to make them smaller would make it easier to differentiate center marks from pencil marks.
Second I would like to see the ability to import puzzles via camera or an imported photo.

I love CTC and I love the dual pencil notation idea of Sven's solver. However, there are a few quirks I think could be improved. Double-tapping an empty cell deselects everything else, but the taps have to be spaced precisely for this to work. There is a little empty space in the bottom left corner of the screen, maybe tapping there could unselect everything.

I would LOVE a way to select all pencil marks of a certain candidate. The other CTC apps do this and it's very convenient.

Double-tapping a filled cell highlights all cells of that number. This is helpful, but it would be great if selecting a digit in the number pad did this. Maybe each “version" of the number pad (number, corner marks, and center marks) could highlight all candidates of that type.

This app is SO CLOSE to being the perfect solver, especially with the ability to enter puzzles. I agree with the other reviewer that an auto-detector would be amazing, but not necessary for a perfect app. The suggestions above (especially the ability to highlight all of a particular candidate) would make it a perfect solver.

Thanks Sven!

I absolutely adore SudokuPad, it is the best user interface for solving sudokus bar none. The app itself has some problems though:

1. The last release was 10 months ago. A couple of killer features from the web version are missing: the letter tool and the new extended color palettes, among others. Please give us an update, Sven!
2. It appears like there is a limit to how many puzzles the app can save: after a couple of months of use, new puzzles stopped getting saved. (Lost progress can be very frustrating!) I've worked around this by deleting and reinstalling the app, but at the cost of loosing all my favourite puzzles and their solutions.
3. Under iOS, MacOS and iPadOS, the UI doesn't work as well as it does on a windows machine. In Safari in particular, some keybindings clash with app shortcuts, making things like the letter tool unusable.
4. The number of clicks to go through from a CTC youtube video to opening and saving a puzzle is far too many
5. Opening a puzzle link twice can lead to an infinite save dialog loop

Rating 4 stars anyway, because when it works, it's excellent.

This app allows you to upload hand crafted puzzles from all over the internet, especially those from Cracking the Cryptic. It's still evolving, though, so some older puzzles won't check quite right, or the rules for variants won't be complete. But the ability to load up and try truly unusual variant puzzles is great, and the interface is solid, with options for how to mark that should satisfy most solvers. A great supplement to Cracking the Cryptic's other collections.

Terrific app. Such a great experience for such a tricky situation— solving sudoku variants on your phone. I've gotten hundreds of hours of enjoyment out of it with no end in sight.

I only wish this app had the letter option that the webapp has! Sven? Any chance?

Thank you for a really great app!

The best part of this app is the auto import from CtC's YouTube channel. Being able to simply import the puzzles makes trying new puzzles a breeze. The UI is also easy and intuitive, though it has some quirks—more later.

The maddeningly worst part of the app is that updates discard all saved puzzles and progress, resetting it to a fresh install. I'd take 2 stars off but that would be a bit unfair. I can't stress how aggravating it is to have some puzzles that you want to save be lost. Tracking those down is not a simple processes, and even when you do, your progress is lost.

The documentation could be improved. There are lots of hidden shortcuts that you eventually stumble upon, but are not obvious; for instances, simple ways to remove pencil marks but not center numbers. It is also a bit jolting since the UI is very different from other CtC apps, but you do get used to the difference after a while.

Some suggested improvements: It would be very useful to allow puzzles to be renamed and also support notes. And, at least for the iPad, supporting split screen would make entering new puzzles from other sources more easy. Also, you cannot use the Apple pencil to click back to the main puzzle list. And finally, the highlight matching cells feature is quirky at best: you often have to double-click several times to get it to work.

After the new update which lets me share puzzles. I opened my app to find all the puzzles I entered and completed are gone leaving only the original puzzles. It's a nice app and I enjoyed adding new puzzles and playing them but it sad I spent all that time adding the puzzles just for them to be gone like that. This and sometimes the app won't let me scroll through my puzzles are the only complaints but they're very annoying issues that led me to write this unsatisfied review.

This app started as a great idea and I immediately bought it when it came out. But over time it has started drifting from the web app and is slowly becoming unusable because the author isn't updating it. For example Killer Cages don't render visibly anymore and every time I report a bug to the author they always say it is fixed in the web app but don't ever port the fox to this app.

Don't buy this until the author starts supporting it with updates.

Extremely disappointed with this app. I was hoping I could use it to build puzzles but this was clearly not designed for that purpose. In the puzzle setting mode you can't add corner or center pencil marks or color cells different colors.

The only think keeping this from a 1 star review is that it does have some good puzzles built in for you to solve, but there just aren't enough of them.

One other complaint - with this app being associated with Cracking the Cryptic, I expected some puzzles to feature sudoku variant rules, or the puzzle setting mode to allow adding custom rules and features to your puzzles (killer cages, thermos, etc.) but no, it's classics only.

Not worth the $5. It would be okay if it started free and featured only the classic puzzles, and the variants and additional classics would be locked behind a $5 paywall.

If you're looking for classic sudoku puzzles to solve, just watch the Cracking the Cryptic videos on classic puzzles and solve those. If you're looking for a puzzle setting tool, just use f-puzzles or penpa.