Map Interaction - Quick Zoom Concept

My issue was the following : how to quickly zoom on a large map, with only one finger.
The goal is to see what's around a specific location, without losing the current "zoom" (for exemple if you want to see what's around 2 different locations).

It's not made to replace the famous "pinch and zoom", it's just another usage that could be useful in some situations.

Usage:
- click on the location
- stay clicked and drag the border to open a mini zoomed map
- drag the mini-map to see what's around. The first clicked location will always stay visible on the map, the size of the map will automatically adjust
- click outside to close it

I also added a GPS / time calculator feature. In this situation, it could be nice to check the closest bus stop for exemple.

It's a little bit different from my previous shot, but the main idea remains.

Feel free to post a feedback, to tell if you think it's useful or not, how to improve it etc...