ZCO has been a very good partner for us. We divided up a large iOS + Android project such that ZCO has handled the user interface while we setup the back-end API. This division of work went very quickly and has led to a very successful project. The ZCO project lead has always been very responsive and quick to discuss new features and any problems that we identify. We continue to work with ZCO regarding enhancements and adding features and would certainly recommend ZCO as a high quality app development partner.