Database Info

[Q] Can you edit/replace the classes.dex on the phone?

I am trying to edit an application however whenever i use apktool (apk manager) or smali/baksmali (jarsigner etc), sign then reinstall the app crashes..
So i am wondering if i can install the untouched package and then edit/replace the classes.dex while it is already installed?
Is that possible? Where exactly do installed apps reside? or do they remain in apk format until run on the phone?
I did search though i couldnt find an answer
Thanking you in advance.

[Q] Sprint App Updater

Is the Sprint App Updater apk for the Shift the same one for the Evo? if not, can someone give me a copy of the .apk file and/or odex. I got a little delete-happy on root explorer. and now my notifications bar is showing that I have an mandatory update available for the VVM that I cant get because im missing the sprint updater.

here is the apk (no odex I could find) pulled from one of the original system dumps posted here early on...

Settings.apk does not run

Hi, I hope someone can help me with my problem:
I run an HTC Sensation, with the latest ICS leak, and have a mod I want to apply, which is an AOSP-ized Settings.apk.
The problem is that if I adb push it onto the phone (/system/app), it does not show in the main menu, like its not installed.
BUT if I first install the stock Settings.apk, boot the phone, reboot into CWM and then flash the modded Settings.apk, it works just fine...
Does the stock Settings.apk alter anything that the second one needs?
I am attaching the modded one if anyone would be willing to help me find the problem...
Thanks!
Kristof

I've got a similar issue.
I wish to install an AOSP settings.apk & settingsUI.apk but I can't find the directory to paste them in. I then made a folder and placed them in there and installed them via ES File Explorer and the changes weren't applied.

[Q] how to make system apk work on other device.

Guys, i want to change the system apk on my other device like messaging. How to make it work? I tried to extract the mms apk from cm10.1 zip ang push it to my other device system>app with permision then reboot. But when i open the messaging app it say messaging had stop. My phone was not cm, still using stock rom original but rooted and running jellybean 4.2.1.
Hope you me guys thanks in advance.

apk and launchers

I am starting this topic to find out some basics information's about apk files and how modify launchers apks before install them.
I use ClassyKitchen to export apk from some roms which have different deisign.
When I try install that apks to my rom (PX6 RK3399 with Android 10) I get an error that cant be installed.
Etc I am trying to install the apks from this rom but I cant.
Has anybody knows what I have to do to the apks files to make it work?
Also can I use a program to remove from the layout of a launcher some widget before I install it?
Thank you so much.