I was trying to port BlackBerry 4.5 compiled application to BlackBerry storm device which is BlackBerry 5.0 device. And also it is touch enabled device. As first issue, I saw app screens were shrunken, there was a blue border around the screen and it was not accepting touch input anywhere. After quick googling, I found, there is a shortcut to make 4.5 compiled application to work on touch enabled device.Such one quick fix is enabling below jad properties to make application touch compatible.
This will enable the 4.5 compiled application touch compatible, User needs to select 'Disabled compatibility' in Options-->applications-->your application to make it work.
Even after this, few issues remain as it is:
1) Touch will work only for native fields. ie., native button and text fields. Touch many not work for your custom field, you need to implement touch event handling.
2) Keyboard will surface automatically after tapping on text field, but it doesn't hide automatically after editing field. This will become more annoying as half of your device screen is covered with the virtual keyboard. This will become major problem if you are using embedded browser field.
3) In embedded browser field, it doesn't open the anchor links automatically, It prompts menu dialog ask for selecting 'Open Link' to open the link.
If we compile 4.5 application with 4.7 above it become touch compatibility by default we dont need to use any jad propeties. But browser field behaviour remains same. I realized, using 4.5 browser field on storm device is unworthy and doesnt provide good user experience. Then I started implementing new "field2.BrowserField" browser renderer. New browser field2 supports complete touch input and renders html surprisingly good. I conclude here, if you are using browser field in your 4.5 code and if you want to run it on storm device, it may not work properly, It is better to consider the option of implementing field2 browser renderer which is available in BlackBerry 5.0.