loaders in android
 

As there are loaders for java applications (for example, Burp Suite), does exist loaders for APKs in android?

to load the apk by 'dalvik.system.DexClassLoader', which is a class inside the android SDK.

i do thought to patch like that ,but i need more time to think and develop loader for apps,
you can patch classes.dex directly application cant detect changes ,u just need fixes checksums and all then even system android OS think its genuine thats what i do with android patchers ,soon will think and implement something to change bytes when app is running ,hope get some time to look upon it,cus this will keep my patches hidden from developers what is being patched

I presume you already know Xposed and are looking for a different approach, right?
If not, have a look here: http://forum.xda-developers.com/xpos...gelog-t2714053
Even if you don't want to use it as is, looking at the resources (sources, examples) might give you valuable inputs.

Mkz i already knows xposed approach and used it for decrypting strings of obfuscated apps

you can inject your codes in the function but i am thinking to do something different ways only with root access