GeoODK problem with the map

Hello, I'm new in this forum..
I have installed Geo ODK because I would like to use it for a field survey in Ethiopia.
We have to collect ground reference data on crops in two irrigated schemes. II have created a new form with all the items required for this activity but I have a problem with Geopoint. I have to save the coordinate of the point, moving the marker in the middle of each sampling unit or field. I don't know why, despite at the moment I have the wifi connection, any map is displayed in the background. Respect to the ODK Collect app, I found this part (GeoLOCATION) of the GeoODK app not so good. I'm using GeoODK Collect 4.1.I wonder why and I would like to know if you can suggest me to download another widget that could be better..