# Known to work
## System
1. [eSpeak](ESpeak.md), offline TTS support for more than 100 languages

## App Stores

1. [F-Droid](F-Droid.md), the OpenSource app store
2. [Aurora Store](AuroraStore.md), googels paly store accessed anonymously

## Browser

1. [Fennec](Fennec.md), firefox for mobile

## Messaging

1. [Signal](Signal.md), messaging via signal servers, encrypted
2. [DeltaChat](DeltaChat.md), messaging via email, auto-encrypted
3. [Telegram](Telegram.md), messaging over telegram-company servers, not encrypted, reads your contacts, not recommended

## Calendar, Contacts & Files

1. Find some ideas described here: [Sync your data](sync_calendar.md)

## Navigation

1. [OsmAnd](OsmAnd.md), uses Open-Streetmap for offline navigation (pedestrian, cycle, car, truck ...), speech output possible.