Amphetamine does one thing (Keep awake). OmniMac does it and adds six more modules in the same app. Here are the facts, no adjectives: usage measured on the same Mac, what each does better and when to pick one or the other.
| Amphetamine 5.3.2 | OmniMac 0.5.1 | |
|---|---|---|
| What it does | Keeps the Mac awake with fixed-length sessions, until a given time, or while something happens (a download, an app running…). | Seven modules: keep awake, ⌘Tab by windows, dynamic notch, window shortcuts, clipboard, tools (OCR, colour, keyboard, microphone) and sound |
| Price and code | Free (Mac App Store), closed source | Free, open source (MIT), no accounts, no telemetry |
| Memory at idle (RSS) | 100 MB | 86 MB (33–37 MB of real physical memory) |
| CPU at idle | 0.000 % | 0.017–0.033 % |
| Size on disk | 7 MB | 16 MB |
| Threads at idle | 5 | 6 |
| Requirements | macOS (see its site) | macOS 14.2 or later, Apple silicon and Intel |
Each app on its own on the same Apple silicon MacBook running macOS 26.5, on 9 September 2026, 50 s at idle with the cursor away from the notch after 15 s of startup. CPU = CPU time consumed divided by elapsed time (ps -o cputime); memory = RSS (ps -o rss); OmniMac's real physical memory (footprint) is 33–37 MB in the 0.5.1 measurement. One run: think orders of magnitude, not decimals. Full methodology and results in docs/PERFORMANCE.md (Spanish); the feature inventory in docs/COMPETENCIA.md.
Free, no accounts. macOS 14.2 or later. Also brew install --cask BySergiMM/tap/omnimac.