# RegEx Knife — user reviews > 26 indexed App Store user reviews of RegEx Knife by Mark Alldritt, rated 4.30/5 from 25 ratings. - Source: https://appshunter.io/ios/app/regex-knife/id894169288/reviews - App overview in markdown: https://appshunter.io/ios/app/regex-knife/id894169288.md - Rating breakdown: 5★ 15 · 4★ 6 · 3★ 1 · 2★ 3 · 1★ 0 ## Newest reviews (6 of 26) ### 4/5 — Please support Chinese. *2024-03-24, version 2.0.2* When there are Chinese characters in the regular expression, they will not be displayed. ### 4/5 — Tool for what? *2024-03-02, version 2.0.2* Developer should integrate this into shortcuts where it will actually be useful for different types of extractions and maybe a different more up to date UI ### 4/5 — Works for basic regexes and that’s it *2022-10-15, version 2.0.2* It’s nice for simple regexes. Unfortunately, I wanted to use a conditional substitution, but the syntax for that varies by engine and the app doesn’t specify what uses. Would be 5 stars otherwise. ### 4/5 — Needs a Dark Mode update *2021-01-20, version 2.0.2* Excellent tool for fine tuning regular expressions with clear visual feedback. The custom keyboard keys are equally clever, but turn invisible in Dark Mode. Fortunately it's usable without them. ### 4/5 — Nice and Simple *2014-10-14, version 1.0.1* I like this app, it's simple and easy to use. It is exactly what I needed to store my regular expressions and as a bonus it allows me to also store test content to help me remember what the expression does in case the title I create isn't clear in the future. The only issues I discovered are the list not refreshing properly when adding a new empty expression and I can't figure out what the substitution template is for. Other than those simple things this app is awesome! ### 4/5 — First! I'm first! *2014-07-17, version 1.0* Works: check. Clear, easy-to-use interface: check. Designed for iOS 7: check. You can collect regular expressions, match them against sample text, and see the result of substitutions. A gesture-based extra keyboard similar to the one pioneered (I believe) by Textastic makes it easy to create and edit expressions and a number of regex options allow you to tweak your results. Two features I'd like to see in the future are a comprehensive reference for regex and the ability to copy code snippets for various programming languages. Even without those, this is a solid app for a 1.0 release. Note to developer: charge something for the app. Perhaps an in-app purchase for saving snippets and/or exporting code. ## Most critical reviews (10 lowest-rated) ### 1/5 — Crashes on run. *2020-07-21, version 2.0.1* Entered one regex and app crashed. Now the app crashes every time I run it. ### 1/5 — Crashes upon opening *2019-06-01* Not much good if it doesn’t open. Crashing on start up on a iPhone 8 Plus. ### 1/5 — Bug report *2014-11-12, version 1.0.2* After saving my own expression, when I click a saved example it loads the wrong example. ### 2/5 — Probably needs an update *2025-07-28, version 2.0.2* This app has been useful, but recently I can’t exit from a custom RegEx back to the main menu. I’m guessing the app needs to be updated. Otherwise I’d give this a much higher star rating. ### 2/5 — Unusable in Dark Mode *2021-12-04, version 2.0.2* As mentioned in another review nearly a year ago, this app does not work in dark mode. Black on black text is completely unreadable. ### 2/5 — Crashes regularly *2019-07-16, version 2.0.1* Lately this app crashes in the middle of use, regardless of text or RegEx patttern. ### 2/5 — Needs an update *2018-07-08, version 2.0* I like a lot of what this app is going, especially things like group highlighting. Unfortunately, on my iPhone X running iOS 11.4, the regex field is hidden by the header, which makes it pretty much impossible to use. ### 2/5 — Crash, crash after crash *2016-03-14, version 1.0.6* You know there is something wrong with the app if some expressions make it go down time after time. ### 3/5 — Crashes *2018-11-04, version 2.0* It crashes very frequently. One time, it always kept on crashing whenever I selected a specific regex. ### 3/5 — Wish it had undo, wish it didnt crash. *2015-08-09, version 1.0.5* I was working on a complex expression when the app crashed. Now I cannot open the saved expression because it will crash the app. Keyboard is awesome! Easy to type complex expressions on the iPad! ## Most praised reviews (10 highest-rated) ### 5/5 — Hands down the best *2024-11-27, version 2.0.2* I couldn’t find it in the AppStore sometime ago. Thanks for RegEx Knife. ### 5/5 — Bug when renaming a new RegEx *2021-09-25, version 2.0.2* You fixed the last bug I mentioned and I really like this app layout. Found two new bugs. One is related to dark theme on iPhone. I can’t see text types in on first type. It is all black on black. It fixes itself after a bit of fiddling. Second is more important. Creating a new RegEx that takes the untitled name then backing out, rand naming it to String.prototype.string and then it reverted to text from a previous entry. When opened it showed different regex than the overview page. It did this a few times until it auto corrected itself. I have screenshots. I can’t reproduce this. These bugs seem to be related to how the app saves on load or on exit? ### 5/5 — Great app!!! *2019-11-15, version 2.0.1* It’s awesome! I wish I would look up simple RegEx documents in the app. ### 5/5 — Great tool *2019-09-18, version 2.0.1* I have been using this for years and it has been so helpful and easy that I just took it for granted and never wrote a review. A great way to test and store regex. ### 5/5 — Great app *2019-07-23* Simple, and all the right features. Gives a really clear view of what any given expression is doing. ### 5/5 — Im using iPhone8plus 256 model- *2017-11-13, version 2.0* This app is very nice, but im not move to LunchViewController->MainVC ### 5/5 — Great Tool *2017-08-10, version 2.0* As the saying goes "does what it says on the tin". I code for work and manipulate vast amounts of information, this tool is fantastic for quickly testing expressions against a data set which is easily manipulated. Has saved me untold time trying to sort out the correct expression. ### 5/5 — Elegant & functional *2015-07-14, version 1.0.5* Impressive and smart implementation of a RegEx tool. "Does what it says on the tin" with style. ### 5/5 — Helps a lot for testing regular expressions *2015-04-05, version 1.0.4* It's a great app to test out regular expressions before I use them in Python scripts or in a workflow. It has become a part of my tools to automate tasks on the iPad. I also used xeger for a while but the editing of the expressions drove me mad. I'm very happy that the app exists at all as there is probably not that much demand for such specialized tools on the app store. In any case, thanks and keep the good work up! ### 5/5 — Really handy *2015-02-21, version 1.0.4* A very nice way to test out regexes on your iPad. The visual feedback for match groups is superb. Easily the best regex app for iOS. --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-11.*