SelfControl is one of the most technically respected tools in this entire comparison set: free, open-source, maintained on GitHub, and built around a genuinely more robust blocking method than almost anything else researched here — it works at the level of your Mac's own firewall, not just inside a single app's permissions. Originally conceived by artist and educator Steve Lambert and developed by Charlie Stigler, it has been maintained and improved by a rotating cast of open-source contributors for well over a decade, with no company or investor behind it at any point in its history.
What SelfControl actually does
You set a blocklist and a timer of up to 24 hours; SelfControl writes rules directly into macOS's own packet-filter firewall, dropping connections to blocked domains at the network level — which means the block affects every browser and app on the machine at once, not just one you've individually configured. It's fully free, with no telemetry of any kind sent back to any server, and the project is openly maintained on GitHub, where anyone can inspect exactly what the software does rather than having to simply trust a vendor's own description of it. The project's GitHub repository shows a long, active history of community-submitted fixes and improvements stretching back well over a decade, which is a genuinely different kind of longevity guarantee than a commercial vendor's continued existence as a company.
Where SelfControl is honestly the better pick
Firewall-level blocking is a genuinely stronger mechanism than app-permission-based approaches — it persists through quitting the app, deleting it, or restarting the Mac, and it covers every app and browser on the machine automatically rather than needing each one configured separately by hand. Being fully free and open-source, with no data collection at all, is also a real, distinctive point in its favor for anyone specifically wary of a commercial screen-time app quietly gathering usage data about them in the background. It's also worth noting that SelfControl's complete lack of any account system or cloud sync means there's simply nothing about your usage that could ever be collected, sold, or exposed in a data breach, which is a real, structural privacy advantage over any subscription-based competitor.
| Feature | SelfControl | Mr. Grummel |
|---|---|---|
| Platforms | macOS only — no mobile app of any kind | iOS & Android (in development) |
| Core mechanism | Firewall-level domain blocking via macOS's own packet filter, for a set timer up to 24 hours | Answer a quiz question from the app's curriculum to unlock |
| Self-bypassable? | Largely no through the intended paths — persists through quit, deletion and restart; some workarounds (changing the system clock, certain proxy/VPN setups) are documented in the project's own GitHub issues | Not yet released — can't be assessed |
| Physical hardware required? | No | No |
| Price | Free, open-source, no paid tier | Not yet announced — join the waiting list |
The one mechanical difference that actually matters
SelfControl's real strength is where its enforcement lives: not inside an app you could delete, but inside the operating system's own network layer, which is a meaningfully harder thing to simply remove than a process you can kill from Activity Monitor. Mr. Grummel has no equivalent — it's a phone app, and it doesn't have access to that kind of system-level hook on either iOS or Android, since neither platform exposes anything close to a user-writable firewall to a third-party app the way macOS does. The comparison really comes down to device and depth: SelfControl goes deep on one platform, Mac, with a genuinely hard technical guarantee; Mr. Grummel goes wide across two, iOS and Android, with a lighter, more portable mechanism. It's also worth adding that firewall-level blocking has a real cost of its own — SelfControl can't distinguish between a genuinely important use of a blocked domain and a distracting one, where an app-level or question-based approach can in principle be more selective about exactly what it interrupts.
Who should pick which
If your distraction problem is specifically on a Mac, and you want free, open-source software with a genuinely hard, network-level block, SelfControl is a well-respected, proven tool for exactly that job, refined by a decade-plus of community contributions. If the problem is the phone in your pocket, where SelfControl has no presence at all and never will given how differently phone operating systems handle network permissions, that's the gap Mr. Grummel is built to fill. It's also worth trying SelfControl specifically if you're a developer or technically comfortable user who wants to actually read the code enforcing your own block, rather than simply trusting a company's description of what its software does. It's also worth remembering that SelfControl's single-platform, single-purpose focus is itself a kind of honesty — it doesn't try to be everything to everyone, it just blocks domains at the firewall level on a Mac, reliably, and has done so for years. That singular focus is precisely why developers and technically minded users keep recommending it, year after year, in a category that otherwise churns through venture-backed apps at a fairly rapid pace.