Regex Playground vs Knockbox
Price, ratings, monetisation and update history for both apps, side by side โ with what reviewers say about each.
Regex Playground
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Regex Playground is a powerful yet intuitive tool designed for developers, data scientists, and anyone working with text patterns. Whether you're validating emails, parsing logs, or extracting data, test your regular expressions instantly with live syntax highlighting and detailed match analysis. KEY FEATURES Real-Time Pattern Matching - Type your regex and see matches highlighted instantly in your test text. No more guessing โ know immediately if your pattern works. Visual Match Analysis - Tap any match to inspect capture groups, match ranges, and see whether you've achieved a full or partial match. Perfect for debugging complex patterns. Pattern Explanation Engine - New to regex? Toggle the explanation view to see a color-coded breakdown of every token in your pattern. Learn what ^, \d, (?:...), and lookahead assertions actually do. Built-In Pattern Library - Jump-start your workflow with 15+ production-ready patterns covering emails, phone numbers, URLs, dates, credit cards, passwords, IP addresses, and HTML tags. Save your own custom patterns and organize them by category. Regex Flags Support - Enable Case Insensitive, Multiline, Dot All, and Extended modes to test patterns against real-world text formats. Test Case Suite - Save reusable test cases with expected outcomes. Run your pattern against your entire test suite and see pass/fail results with a visual progress indicator. Essential for regression testing regex patterns. Smart History - Your recent patterns are automatically saved so you can iterate quickly without retyping. Favorite patterns you use daily. DESIGNED FOR DEVELOPERS - Clean, distraction-free interface optimized for focused work - Monospace fonts for pattern readability - Dark mode support - No account required โ all data stored locally - Works offline completely WHO IT'S FOR - iOS/macOS developers parsing text data - Backend engineers validating API inputs - Data analysts cleaning datasets - Students learning regular expressions - QA engineers writing test validations Stop switching between browser tabs and IDEs. Build better regex patterns faster with Regex Playground.
Knockbox
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Knock once, and your phone buzzes. Knockbox turns one HTTP request into a push notification on your iPhone. Anything that can send a request can reach you: a deploy script, a cron job, a monitoring check, a CI pipeline, or a coding agent that has just finished a long task. If it needs your go-ahead before continuing, it can wait for your answer. curl -d "Build finished" https://your-server/api/v1/send/YOUR_TOKEN THE SERVER IS YOURS Knockbox is the client for a server you control. The server is open source and runs on a VPS, a NAS, or a Raspberry Pi at home. It holds its own Apple push key, so a notification goes from your machine to Apple and then to your phone, without passing through anyone in between. If you would rather not run anything, open knockbox.miramiao.com on your iPhone and you are connected โ no sign-up, no password. WHAT A MESSAGE CAN CARRY โข A Markdown body with headings, lists, links and syntax-highlighted code. โข Images, shown in the notification and kept with the message. โข Long text. The body is fetched as the notification lands rather than packed into it, so there is no length limit to work around. โข A title, a channel, and an interruption level: quiet, normal, or time sensitive when it has to break through Focus. REPLIES โข The sender can attach a set of options, or allow a free-text answer. โข Answer from the message itself. Your server posts the reply back to the address the sender gave, signed, and the sender takes it from there. โข The sender can set a deadline. After it passes the message reads "Reply window closed" and the server stops accepting โ you are never left thinking an answer went through. โข A message is answered once, and the answer is the same across your devices. CHANNELS โข One token per channel, so a noisy monitor and a personal reminder stay apart. โข Muting a channel truly stops it: the mute lives on the server, so nothing is sent at all. โข Search your history, mark as read, delete a message, or clear a channel. Deletions are real, on the device and on the server. MORE THAN ONE DEVICE Pair a second iPhone or iPad from a device that is already connected. Both receive everything and share read state. TRY IT WITHOUT A SERVER Demo mode fills the app with example messages and sends a sample notification, so you can see how it works before setting anything up. FREE, AND THAT IS ALL No ads, no analytics, no account with us, no in-app purchase, no subscription. The app is free and the server is open source. Server source code: https://github.com/aichy126/knockbox Public server: https://knockbox.miramiao.com How to send: https://knockbox.miramiao.com/docs Questions: info@miramiao.com
Screenshots
Verdict
Regex Playground and Knockbox are too close to call on the numbers: across 5 compared parameters โ price, ads, in-app purchases and device support among them โ neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.
Scored on Price ยท Rating ยท Positive reviews ยท Number of ratings ยท Update frequency ยท Ads ยท In-app purchases ยท Monetization ยท Best chart rank ยท Devices ยท Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
| Parameter | Regex Playground | Knockbox |
|---|---|---|
| Price | Free | Free |
| Update frequency | โ | Daily |
| Ads | No | No |
| In-app purchases | No | No |
| Devices | iPhone, iPad | iPhone, iPad |
| Requires iOS | 18.0 | 17.0 โ better |
| Further details โ not scored | ||
| Size | 2 MB | 7 MB |
| Age rating | 4+ | 4+ |
| Developer | Nirav Parmar | ่ ่ |
In-app purchases
Regex Playground
No in-app purchases
Knockbox
No in-app purchases
Questions
Is Regex Playground free?
Is Knockbox free?
Do Regex Playground or Knockbox have ads?
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