I’ve been working on App Tamer 3 for quite a while, beefing up its internals to make it more robust and more efficient, while adding requested features and improving the user interface. It’s finally ready for public testing – I’m excited to hear what you think!

To get a copy of the beta, go to the Beta Testing Page.

If You’re New to App Tamer

App Tamer displays and controls how apps and services are using your Mac’s processors. There are hundreds of separate processes at work on your Mac – some very apparent, like Safari, and some that run in the background to support apps and the operating system.

All of these processes need processing (CPU) time to do their jobs, and macOS typically manages them fairly efficiently. However, it doesn’t always prioritize those jobs optimally. Spotlight, Time Machine, or a browser running in the background may use processing power that could be otherwise allocated to a task that’s more important to you.

App Tamer lets you take charge of processes that are consuming CPU cycles, slowing them down so they don’t impact your work as much. It can also shift processes to slower, more power-efficient processor cores, ultimately saving power (and battery runtime, if you’re using a MacBook).

And yes, if you’ve encountered a bug in macOS that inexplicably drives a service to use 100% or more of a CPU core, App Tamer can throttle that back to whatever CPU usage you decide to give it. Is photoanalysisd churning away on your Photos library to the detriment of all else? Set App Tamer to run it on the efficiency cores and give it no more that 10%.

New Features and Improvements

Here’s a quick run-down of the major changes in App Tamer. There’s lots more, but these are the highlights.

CPU Temperature

App Tamer now displays CPU temperature so you can see how CPU load is affecting temperature. This lets you make intelligent decisions about which processes need to be slowed down to keep your Mac cool and running quietly. And yes, you can automate app management based on temperature with custom rules (below).

CPU Usage Graphs with More Detail and Accuracy

App Tamer 2’s graphing of CPU usage was pretty rudimentary. Version 3 displays usage data more accurately with customizable colors, automatic scaling and properly annotated axes. It gives you more insight into what’s happening on your Mac.

Switchable Profiles

App Tamer’s ability to fine-tune priorities for apps and background processes is great, but up until now you could only set up one configuration of CPU limits, auto-hide, auto-quit, etc. Now you can create different settings profiles and switch between them. This lets you customize how apps are managed to fit different needs and workflows.

Custom Rules and Focus Filter

You can now set rules to switch between different settings profiles based on a number of criteria. Do you want to throttle CPU-hungry processes when you’re actively working in Final Cut Pro, but let them run when you’re using other apps? Slow down an app when the CPU temperature goes above 70°C? Automatically hide browsers when you’re busy writing? You can do that and more.

And if you use macOS Focus modes, App Tamer includes a focus filter that lets you switch to a particular settings profile when you enter a Focus mode.

All App Settings in One Place

You can browse and modify all customized app settings in App Tamer’s Settings window, making it much easier to review and change how you’re managing each application.

UI and Feature Improvements

I know it’s a cliché, but there are too many to mention. The UI works more smoothly, is translucent and better organized (but no, it’s not been rewritten in Swift UI – App Tamer needs to be compatible with very old systems and has to work consistently across all of them). The contextual menu in the process list offers process details plus web search if you want to know more about a process. You can throttle background processes like menu bar apps. High-CPU warnings are smarter. And a ton of other stuff.

Check out the Beta Testing Page for the long list of changes and fixes.

Under the Hood Improvements

App Tamer’s process monitoring and control engine has been revamped, making it both more efficient and more robust under high CPU loads (because you’re trying to manage your maxed-out Mac, right?). It’s also compatible with the new M5 CPU architecture in the latest Macs, and manages multi-process apps like web browsers and the Spotlight indexer more effectively.

This entry was posted on Friday, April 10th, 2026 at 6:45 pm and is filed under App Tamer, Development. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.