Do single and multi-language translation of chat messages
1) Single language translate on web interface
The first idea is to be able to have the messages translated into another language, at least the Google translate languages, so you can work in the field with a team working in a different language (or, if you are like me, you know a language but perhaps not that well). I would be working with women in the Congo who are texting in French, and I would write them in English (translated back to French).
2) Multi-language translate on web interface - so you can communicat with people in many languages.
A more sophisticated option: I am imagining a large international meeting where you want real grassroots participation. There is a discussion and people around the world are asked questions that arise during the discussion over text. Their messages are sent back in and translated into the language of choice on the screen (English, whatever)... All messages are sent back in the preferred langauge of the user. One challenge here is that there will be people who do not speak any of the Google translate languages.
3) Text message translate on phone
A third use case. You have two women's groups near a border area whose int'l languages are different (for instnace, uganda and congo - french and english). the women on one side write in French and the others receive their texts translated into English (and visa versa). They may set a default language for translating.
And of course start with translating GeoChat itself.