Sometimes, it may be interessant (and perhaps easier and faster) to develop web-apps instead of native mobile apps. But the main issue is about the appearance problem. Nowadays, all those problems are minimized with html5, css3 and (eg. jQuery) JS libraries.
Today I'm not presenting any own source code, I just share a jQuery plugin that I found on web, to avoid appeareance problems on web-apps (at least in selectors). Their site is Mobiscroll, and you can find some sampleson their demo page . With that plugin, you can present simple date (or other selector) input forms, looks like:
And of course, as always with jQuery usage ease and MIT license.