Automatically show results from my location(s). You can obtain the location(s), easily, from my activities, or by adding a "my location(s)" to a user's settings.
That would, obviously, save some clicks and provide immediately-useful information to a user - better usability.
(Alternatively, you can consider saving the last view to do something similar).
In addition, it would be great if you add the ability to look for newly added activities. Either by sort or filter, or possibly use a different color-code marker on the map.
