> Given no further information what do you think?

Even with further information, it'll ultimately have to be what both of you are comfortable with.

Granted, you've done a lot of hard work single-handedly but do not underestimate the value/importance of implementation, especially in a startup environment.

Also, if you all are going to need/raise funding, you should give some consideration to the currently prevailing norms of founder - co-founder ownership patterns acceptable to the funding sources and keep that in mind while deciding on this.

HTH