Hello, I can build a fully responsive and user friendly ecommerce app (Android and IOS) for buy and sell of used goods which will have similar functionalities as in OLX app as per your requirements. I am senior mobile app developer with loads of working experience with ecommerce/ online store apps and I am absolutely sure that I can do the project very well. Do you also want me to publish the apps on Google Play store and App store?
Lets have a quick chat to discuss further.
I have extensive experience in designing and development of Websites, Mobile Applications, Management Systems and E-commerce or Online Stores Solutions.
Kindly have a look at my Portfolio and Client's reviews via this link,
https://www.freelancer.com/u/junkyfunky
Thanks,
Faizan A.