I had to figure out how to build a simple app at work the other day.. so decided to look at all the online webapps that do it for you using content from your website, blog or other feeds.
You'll find a bunch of them if you google, but this one works well(and wasn't blocked by my office firewall).. has a lot of customisability and covers most platforms(android, ios, windows phone, bada..). Its called Conduit, try it at mobile.conduit.com.
Step 1: Heres what you need
2) some image editing tools and skills
3) content in the form of a blog, twitter, flickr, youtube, etc.. anything with an rss feed will work.
4) a device to test or use the app on - PC/MAC Browser, Android device, IOS Device, Windows Phone, Bada
for android and windows phone the site generates the installer file(.apk etc.) that you can immediately test on your device.
However for IOS and Bada you need to get a dev license
6) If you want to publish your app on any appstore/market you'll need Developer licences for android($23), IOS($99), Windows Phone($99), Bada(free) . i have two android devices and lots of friends and coworkers with android devices as well.. so got the android license.
Step 2: Step 1
and punch in the url to your web page, cms(blogs etc.) based pages work best.
Press the "Create" button.
Step 3: Step 2
from here on its pretty simple.