COVID-19 Contact Tracing app for iOS 13
- Built with React Native and uses Redux
- Communicates with back-end server
(filigino/trace-server) via REST
API
- Server stores data via NoSQL MongoDB database
- Uses tzachari/react-native-contact-tracing for Bluetooth contact tracing
- Splash icon made by Freepik from www.flaticon.com
- Uses Bluetooth to detect phones of other users the user has come into contact with
- Supports Push Notifications on confirmed Exposures to other users that have tested positive for COVID-19
- Supports Background App Fetch to check for new Exposures every hour
- Uses a decentralized network architecture with most data storage and
processing done locally on the phones to protect users privacy
Note: Does not implement Apple/Google's Exposures API
Follows Apple and Google's contact tracing scheme:
Using the tzachari/react-native-contact-tracing library, when two phones running Trace detect one another via Bluetooth, each phone:
- Generates a unique 24 digit string, which it stores locally in a list of
myIdsand broadcasts the ID to the other phone - Receives the other phone's ID and stores it locally in a list
of
otherIdsNote: The Apple and Google contact tracing scheme specifies that each phone continually broadcasts its own unique ID until that unique ID is updated every 10-20 minutes. Trace has two IDs generated each time any two phones come into contact - one ID for each phone.
Upon confirmation that a user has tested positive for COVID-19, that user
should self-report their infection through Trace at which point, the
previous 14 days of the user's myIds (IDs it has broadcasted to other phones
the user has come in contact with) will be submitted to the Public Health
Authority.
Periodically, each phone running Trace downloads the list of IDs that
corresponds to users that have tested positive for COVID-19 in the last 14
days. Each phone will then compare its list of otherIds (IDs of phones of
others users the user has come into contact with) to the infected list and
notify the user of any matches (i.e., potential exposures).
Note: No user information is ever stored by Trace or at the server. Only IDs consisting of randomly generated numbers and letters are communicated and contain no information pertaining to a user's name, email address, location, etc.
All IDs (myIds and otherIds) and exposures older than 14 days are deleted:
- Every hour
- Every time Trace is launched
myIds older than 14 days are also deleted:
- Right before a user self-reports their positive case of COVID-19 (to ensure only IDs from the last 14 days are sent)
otherIds are also deleted:
- Upon Exposures confirmed by a match between
otherIdsand the list of infected IDs (to prevent duplicates)
IDs corresponding to users that have self-reported are deleted from the server:
- 14 days after they were initially reported
In order for an app like this to allow for successful contact tracing and to appropriately warn users about potential exposures, the following must occur:
- All members of the community must download the app to their smartphones
- Users must always keep the app running, at minimum, in the background (or at least have it running when they are outside of their homes and could potentially come into contact with others)
- Minimal delay between a positive test result for COVID-19 and self-reporting that positive result through the app
- Minimal delay between a positive test result for COVID-19 and self-isolation (should not come into contact with any other users from then on)
- All IDs generated exchanged between phones must truly be unique
- Add Offline mode so app is functional without internet/server connection
- Configure permissions alerts for Bluetooth usage
- Add modal for details of each Exposure
- Connect to an HTTPS server through SSL