Javascript UI mobile app developer for sports matching app (phonegap,5app etc)

I work withing software dev industry and have good knowledge and am the SME within this app I need. I am looking for a Javascript mobile app developer required to build social media matching app using facebook, google + and or twttier api for android and apple mobile devices.
I have full requirements and designs which are very current and fit some of the current contemporary style under google and apple stores.

Ideally wanted to use something like phonegap, 5app to create the app. Want it platform independent so I can roll it out across other platforms at some point.

Looking to build a good working relationship with someone that can challenge my requirements and be really enthusiastic about this and bring value to this app. Someone having good network contacts would be desirable. If this sounds like you then please enquire.

See the rough user journey below:

1. Welcome screen with joining Page button
2. Sign in using facebook, google + (possibly twitter)
3. User selects role type – Personal or professional buttons
4. Welcome page showing user login from screen 2 and a search and goal button
5. Select what you are doing, there will be a main and sub catergory
6. Select a date and time
7. Set a place – this will be using one of the api location/gps settings
8. Goal is set
9. User searches – page comes back to screen 4
10. Search criteria – use tinder style sliders for when, who and where
11. Matched page – shows user, name, role and a connect requested, once the user is accepted they can chat

Notes:
There will be some form of chat required once the user connects to a match, I want the lowest cost solution in using this as this first version is the MVP.

Questions:
By using cross platform development do you see this having problems with the backend?

What are the pros and cons by using cross platform rather than using javascript for android and operation c for iOS?

Do you have sports knowledge, why should I hire you?

Will you be able to make my visual design come to life?