Yes. SJ CRM works in any modern mobile browser (Safari on iPhone/iPad, Chrome on Android). The interface adapts to small screens.
Native iOS and Android apps with offline sync are in active development — they’ll be a free addition for active subscribers when ready.
A native desktop app for Windows, Mac, and Linux is in active development — same idea as the mobile apps: distraction-free, offline-capable, syncs when you’re back online.
For now, the web app works on every desktop browser.
Any modern browser updated within the last 2 years: Chrome, Firefox, Safari, Edge, Brave, Opera. Internet Explorer is not supported (and Microsoft no longer supports it either).
For best results, keep your browser updated.