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As there is no internet deployed back-end, the devices needed to be USB connected, which limited the testing range.
Human error in distance measurement +/- 2cm
Only Android and two types of device
Method
Built and installed APK via USB to both phones
Over 45 minutes (with a tape measure) moving the two devices running the app around at distances between 0 and 320cm (changing distance every two minutes)
Extracted the readings from the phone databases manually (method)
Observations & Analysis
It is notable that no new permissions were requested by the phone.
Detailed Results
Device A
[{""latitude"":41.3986053,""longitude"":2.159144,""time"":1588416619345},{""latitude"":41.39861143255973,""longitude"":2.1591758894271402,""time"":1588416964271},{""latitude"":41.3986111,""longitude"":2.1591477,""time"":1588417382311},{""latitude"":41.39884529419205,""longitude"":2.1591677377011083,""time"":1588417707904},{""latitude"":41.39824724790695,""longitude"":2.1587165941002344,""time"":1588418190144},{""latitude"":41.398746510869785,""longitude"":2.1590672619422353,""time"":1588418516542}]
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