# External notification service **URL:** \ **Category:** Development\ **Created:** [November 20, 2017, 8:01pm UTC](https://bisq.community/t/external-notification-service/3476 "2017-11-20T20:01:41Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![ManfredKarrer](https://bisq.community/user_avatar/bisq.community/manfredkarrer/32/26_2.png) [@ManfredKarrer](https://bisq.community/u/ManfredKarrer)\ **Post date:** [November 20, 2017, 8:01pm UTC](https://bisq.community/t/external-notification-service/3476/1 "2017-11-20T20:01:41Z")
We might have found a way how we can support external notifications while protecting privacy. Please read here the basic idea and provide feedback: > > > We would like to have a notification system so that users get informed about imp…ortant event from their Bisq app in other channels like a mobile app, email or others. > > This has to be implemented in a way which protects the users privacy. > An idea discussed with @cbeams and @ripcurlx is to use a http server running as hidden service where users send the notification events from the Bisq app and that service is set up to use notification infrastructure (Google, Apple push notifications, email,... ) to push the notification to the user. The user has to set up their "account" with that service where they connect a UUID with a mobile number (and/or email). A private key for encryption will be needed as well (pairing of GPG private key between Desktop app and mobile app can be done with a QR code). The Bisq app sends then a message on defined events like "open offer got taken" to the service and the the service sends the notification to the mobile number/email matching the UUID. > Those messages are encrypted. > We could allow optional plain text, but the main message has to be encrypted so the service cannot derive information out of it. To use plain text (headline like "offer taken") would has the benefit that the mobile device can display that in lock screen. The encrypted message can only be decrypted once the user opens up the mobile Bisq app. The plain text feature would be optional. > > The UUID and GPG private key should be decoupled from any other app data (onion address, encryption or signing key) to allow that the user can re-assign any time their UUID and key with a new mobile number or email address. > > The registration of the UUID/mobile nr./email should be done from the Bisq app to benefit from the privacy provided by the hidden service. > > For email the service operates an email service to send out the message to the registered email address matching the UUID. The user need to have GPG if he uses encrypted messages, otherwise he would only receive the optional plain text message. > > The operators of the service is a BSQ contributor and get paid for his service. The role is bonded with BSQ. The can and should be multiple services and the message passing should circulate so that one service never receives all messages of a user (with plaintext there is a privacy issue). > > Maybe we can find a solution to also provide privacy with the optional plain text messages? Any idea how to achieve that would be very welcome! > > Tasks: > \- Define and fine-tune concept, specially in regards to privacy > \- Research notification infrastructure and requirements for Apple and Google. > \- Research alternative notification infrastructure > \- Research email notification > \- Research implementation technology (native app or write once run everywhere frameworks) > \- Build service node > \- Build basic prototype for Android and iOS. > > This app could be the seed for a more sophisticated mobile app which adds trading features over time. So it should be taken into account this future perspective when selecting solutions. If you are experienced with notification infrastructure and mobile development would be great to hear your ideas!