FRITZ!App Fon

FRITZ! GmbH

About this app

Easy calling with the landline network

Make calls at home conveniently using your smartphone over your landline telephone numbers - anywhere in the Wi-Fi network of your FRITZ!Box. With the FRITZ!App Fon you benefit from the landline rates; for many providers even from flat rate telephony. HD telephony provides for crystal clear voice quality. Thanks to support for Bluetooth headsets you can enjoy complete flexibility for everyday calling and for working from home. The latest technologies mean that the FRITZ!App Fon works invisibly in the background no matter what the battery status.

The FRITZ!App Fon guides you through the easy Configuration. Simply log in by entering your FRITZ!Box password, selecting one of your landline telephone numbers, and them confirm: your smartphone is ready for landline telephony. Once it has been configured, the FRITZ!App Fon makes your smartphone ring immediately for incoming calls, just as if it were a FRITZ!Fon, the intelligent all-rounder for your home network with FRITZ!. Incoming calls ring simultaneously on your telephones and smartphones. You decide which device should pick up the call. If you would like your smartphone to ring only for certain landline telephone numbers, select only these numbers in the settings of FRITZ!App Fon.

The FRITZ!App Fon is the ideal telephony extension for your FRITZ!Box. Be it a handset for the new roommate in your shared apartment, an additional telephone for working from home, or the convenience of the smartphone that's always handy: with the FRITZ!App Fon you always have a practical solution in no time at all. It is easy to use the FRITZ!App Fon on multiple smartphones.

FRITZ!App Fon functions at a glance

Makes telephone calls over the landline with your smartphone
Top voice quality thanks to HD telephony
Supports Bluetooth headsets
Accesses the telephone books on the FRITZ!Box and smartphone contacts
Displays the names of known contacts during calls

Ratings and reviews

The app is usable and feature rich. However, the app will not create notifications (unlike say WhatsApp) for missed calls even if it was in WiFi-range of the Fritzbox during the missed call. I use Xiaomi phones and don't keep the app running after making calls. Edit: regardless of the comment by AVM below: the app does not create notifications for missed calls visible on the lock screen. Confirmed on two different phones made in 2021 and 2025.

I have imported my letsencrypt certificate in the fritzbox, but in all fritzbox android apps I can only add the fritzbox by ip. So I get a certificate warning every time I open the app, there is sn option to trust it but your choice is not saved so it's asking every time. I mean this is really poor considering I have to trust these people with my network security. Edit: this has not been solved in one year, I have been asked to report through the proper channels so it can be officially ignored

I had high hopes for this update. The interface is definitely better - a more modern look. Sound quality is a bit better, but still not up to the standard of a DECT phone on the Fritz!box system. Two issues: (1) lag/latency which means you end up interrupting the person you are talking to on the phone (2) voice distortion - making you sound like a Dalek. Sadly there doesn't seem to be any way of tweaking the sound through settings short of of trying a reinstall. In fact there don't appear to be any technical settings available at all which is strange on a VOIP phone.

What’s new

NEW: Callers can be held
Improved: Improvements to stability and details