There are pros and cons of each software option. Resulting solution depends on requirements. Need more info regarding pre-requisites. Talking never hurts, initial conversation is free.

It's the product itself, the idea and accuracy of customer reviews, specifically whether there's a match for end client. Consulting on top of it can be used as one of additional nice-2-have features, but not primary focus. To make a parallel, some time ago there were info call centers, most of them used Internet as a source of information and charged customers for using their phone line (sort of wrapper, mediator between source and customer). So once customers started using Internet and bought smartphones, these info services became no longer required.

The best approach would be to split this project into smaller tasks and ask dev team to prepare a ballpark estimate. Can't provide accurate answer as it really depends on their individual skills/performance. However my iOS team would be able to do this roughly within 1-1.5 months. Please let me know, if you need any further support. Thanks.