If you are including the OLC library in your project directly, you will be able to calculate a plus code from the user's device location, and also translate any plus code back into latitude/longitude coordinates. All on device, without any need for connectivity: https://github.com/google/open-location-code/tree/master/java
Calculating the distance could then be performed on the lat/lng coordinates using something like the Haversine formula (https://en.wikipedia.org/wiki/Haversine_formula) - or, alternatively, following something like this wrapper class I created a while ago if very rough approximations are good enough for an offline, step-by-step navigation: https://github.com/bocops/open-geotiling/blob/master/java/org/bocops/opengeotiling/OpenGeoTile.java In any case, displaying the current and destination plus codes while the user approaches might help them find the exact location more easily. On Tuesday, December 3, 2019 at 6:20:27 AM UTC+1, Abizer Jafferjee wrote: > > Actually, connectivity is a big issue because mobile data is still > relatively expensive in Tanzania. > > Currently the QR code has a deep-link back to the digital address within > the app. > > One option I thought of was to create a USSD application which can be > triggered from the app and would retrieve text directions to the location. > > I like your idea about giving some helpful information. How would I > calculate the distance between two plus codes? And how would I know the > plus code of the location the user is standing at? > > Thanks Andres > > On Monday, December 2, 2019 at 3:52:54 PM UTC-5, Andreas B wrote: >> >> That makes sense, thanks for the explanation. I agree with the conclusion >> that plus codes aren't that useful in any scenario where both users are >> online, and can just access a database with all the necessary information. >> I wonder if it would make sense for your app to use plus codes as a >> fallback for scenarios where one or both users sharing an address are >> currently *not *online? >> >> For example, I assume the QR codes displayed by your app contain an ID >> value referencing the address data. If the QR code *also* contained a >> plus code directly, that could be used to at least display *something* >> even if the user is not currently online. >> >> Would a statement like "1.5km to the north-west - more information if >> you're back online" be useful, or is connectivity not an issue that needs >> to be solved in your app's case? >> > -- Public site: http://www.openlocationcode.com/ Github project: https://github.com/google/open-location-code Demo site: http://plus.codes/ --- You received this message because you are subscribed to the Google Groups "Plus Codes Community Forum" group. To unsubscribe from this group and stop receiving emails from it, send an email to open-location-code+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/open-location-code/cd29bc4f-0eb6-4da4-b168-b7ce12080888%40googlegroups.com.
