All methods are accessed as https://www.dopplr.com/api/.

Any URL can be supplied in JSON or XML - add format=xml or format=js to the query string. JSON format also supports javascript callback wrappers - add callback=xyz to the query string.

Traveller methods (called as /api/methodname?traveller= to apply them to another traveller, or just /api/methodname to apply them to yourself): fellows, traveller_info, trips_info, future_trips_info, fellows_travellingtoday, tag, location_on_date

Trip methods (called as /api/methodname?trip_id= ): trip_info, add_trip_tags, add_trip_note delete_trip

City methods (called as /api/methodname?geoname_id=): city_info, add_trip

Search methods: search_ city_search_ traveller_search

Tip methods: tips add_tip

Other things: update_traveller

(I'm currently documenting these methods, expect the odd broken links/pages till I'm done)