Compare software

HetrixToolsNightbell
Freemium

Free tier with 15 uptime and 32 blacklist monitors; paid plans add more.

 Free

Free and open source under the Apache 2.0 licence.

Web Android
  • Generous free tier for uptime and blacklist monitoring
  • Checks from up to 12 locations
  • No server or account needed
  • Tokens and history stay on the device
  • Hosted only, with no self-hosted option
  • Requires an account
  • Checks only run while the phone is on and connected
  • Not available on Google Play
Web application, Hosted service Downloadable app
Closed source Open source
License not stated License: Apache-2.0
Account needed No account needed
Needs internet Not stated if it works offline

Checked September 23, 2026

Checked October 2, 2026

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