Help selecting open source cross platform mobile application development

Team,

I have need to write small application for my church that would be used for an event that is coming up on August 20th.
Application is to help navigate flow of guests used by set of volunteers. I need some help in selecting right open source tool that would accomplish this with relatively low learning curve.

I Have done some heavy programming with C for years but very low to moderate in writing javascript and java.

For what is intended, there is no need for native calls or sensors to touch. its going to be screen driven app mainly to help ease of flow for the convention that is attended by nearly 7000 people.

Any suggestions?

Is there open wifi at the church? If so, are the specs required for the application such that it could be accomplished by a webpage (which would likely resolve cross platform concerns)?

Thanks for the reply and you are right, HTML/PHP would work fine and should resolve the cross platform concern.

Conversion is at the curtis culwell center in Garland with no open wifi. will use dataplan on the phone.
There is a bit database interaction that we can manage using php on backend I think.

try mit app inventor http://ai2.appinventor.mit.edu/

steps:

  1. create an app that has a webview widget
  2. set url to your single page web app
  3. build then distrib your apk