Hello Sir/Mam, We have Already developed several applications using xamarin.
I have read your requirement and understood that you are looking for an experienced mobile app developer to develop an App(in Android & iOS) for your EventTitans website.
I have checked your three attached images & also know about your website & understood that which type of functionalities you want in your app & yes, will be able to provide all services which you mentioned in your post.
And will be happy to develop an application for you according to your need & Also have some more ideas to implement on that & make it best from the crowd.
So, Let me inform you that we have a skillful and experienced team and we work on all technologies with 8+years of experience who have already developed lots of Websites, Applications(in Android & iOS), and System as per client's requirement & within a given time.
Also, a developer is familiar with all technologies but they have must expertise in Android, C#, iPhone, Xamarin, Graphic Design, web design, HTML, PHP, Wordpress, & etc...
Already we have developed several projects which are quite similar to your need so if you want to see our previous work will be happy to show you via personal chat & explain in details.
And Yes, Can you please share your Detail requirement Document So I will refer it & let you know if I have any query & will provide a precise timeline & fair budget.
Awaiting your positive response
Best Regards
Monali