Part A - Slow Blackberry performance
When you say that the motion is 'almost normal' when running on a desktop, does this mean that the motions is still somewhat sluggish?
Checking out the benchmarks found here:
http://www.roylongbottom.org.uk/android%20benchmarks.htm[
^] (Yes - I know a blackberry isn't an android - look for QU-S4 figures - Qualcomm SnapDragon4 - the cpu found in newer blackberries)
We can see that the power of the snapdragon is capable of speeds upto about 300 MLPOS, while a Core I3 as found in this laptop has speeds of about 2710 MFLOPS as measured by MAXFlops.
Straight away, one can see that there IS about 10x the processing power in this laptop over a newish Blackberry.
[EDIT: On my Huawei Sonic Android phone, I get a similar decrease in Canvas and JavaScript performance when going from desktop -> phone]
Part B - Update in response to button press
It's a bit hard to say without seeing your code. From the sounds of it, you may be checking the value of the text-boxes during your drawing loop. If so, a pair of global variables to hold the dimensions may be helpful. You can initialize the vars and set the values to the text-boxes. From there, instead of submitting the form, you can update the global variables whenever the button is pressed. (After they've been sanity-checked, of course)
If you show your code, you'll likely get a better answer.
EDIT: Dammit! Now I look like a necrophiliac... forgot to check post-date..