I made this chart for a presentation at the Berkman Klein Center
| Telegram | Signal | ||
|---|---|---|---|
| Source code | closed source | open source | open source |
| Api | none | various | library |
| Encription protocol | state of the art | self made | state of the art |
| Contact list location | cloud | cloud | cloud, encrypted |
| Forward Secrecy | yes | yes | yes |
| Database | phone storage | cloud | phone storage |
| Backup capability | Icloud or Gcloud | builtin | none |
| Revenue | ads (Facebook) | donation based | donation based |
| Federation | no | no | no |
| Alternative download location | website | F-Droid | none |
| Uses third party services | no | no | Google Cloud Messaging |
| Servers location | US | Russia | US |
| Tied to mobile number | yes | yes, but nickname available | yes |
| Desktop client | no | yes | no |