I already updated to 4.4.2 but what's app shows me the same erorr as before when i try to install it.
Do i have to factory rest the phone after converting to ART.
Another thing, when i tried to go back to delvic and install what's app it showed the same error as on ART
root your phone. open root explorer or adb shell
if root explorer:
go to folder data, then go to folder data again(yes there are 2 folder datas, one within another)
delete any folder with whatsapp on the name (i think its com.whatsapp.something)
if adb shell:
type su and grant permissions on the phone.
type cd data/data
type ls
(it will show all files/folders)
get the folder with whatsapp name on it
and do
rm com.whatsapp.something/* (the name is different, but it must have whatsapp on the name)
rm com.whatsapp.something/*/*
rm com.whatsapp.something/*/*.*
rmdir com.whatsapp.something/*
rmdir com.whatsapp.something
exit
exit (again, because the 1st one just leave out of root mode)
reboot phone and try to install whatsapp again(dosent matter - art or dalvik, it must work).