In Map Mavin you can zoom to entire layers (click Zoom to Layer in the hamburgeler drop down to the right of any layer's name) and also to individual points, lines and polygons (features). To do so, open the Attribute Table for the layer in question (also found in hamburgeler) and once it's popped up below in the toolbar simply click the features you'd like to see. The map will automatically pan to and zoom over the given feature.

Update, September 27th, 2018: Editing attributes can be saved at any time with a newly added SAVE button.