General app creation advice

Hi,

I was just wanting some general advice on how to approach creating an app which is required for iOS and android on phone and tablet.

The app's functionality would be as follows. When you open the app it shows a random "Tip of the day" which is about 5 lines of text. There is a button called "Next tip" that when you press shows a new Tip of the Day replacing the last one. There is a pool of 150 tips. And that's it.

Distribution of the app would be through either 1) Email link to download app 2) Download link with the apps hosted on my webspace.

As the app needs to be both android and ios, I need a way for the app to be convertible from one to the other without there basically being double the work.

So the kind of advice, I was hoping for would be, for example........ "you could create the app in xxxx, convert it to android in xxxx, use xxx database, it would prob take a single developer xx days to create/test."

Thank you