Compare software

Polar Flow vs Intervals.icu: catalog facts
Polar Flow	Intervals.icu
Free Free to use with Polar devices.	Free Free to use.
Android, iOS, Web	Web
Syncs data from Polar watches and heart-rate monitors Available on the web and on phones	Detailed fitness, fatigue and power curve analytics Separate zones and metrics per sport
Only useful with Polar hardware Web service was under maintenance when checked	Web only, requires an account Analytics depth can be a lot for casual users
Downloadable app, Web application	Web application
Closed source	Closed source
License not stated	License not stated
Not stated if an account is needed	Account needed
Not stated if it works offline	Needs internet
Official website Full listing and sources Checked September 23, 2026	Official website Full listing and sources Checked September 23, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.