I got an iphone4s. Its is lock with icloud activation lock. Is there a way i can reset my phone without plugging into the computer?

SOURCE: I have an iphone 4s locked through icloud ,is it

hello !
unfortunately there is no way to bypass it till now,
the only solution is to replace the mother board which seems that you need to buy an other iphone
for Iphone 4 yes check this

SOURCE: How to reset icloud id on a iphone 5 that i buy on ebay?

You really bought a phone that is locked. Perhaps even the owner does not know you have it.
Only the person with the Apple id, ending with .mac.com knows the password. If he is willing to give you the Apple ID and the password, this phone was setup with, you can unlock the phone. If not, you won't be able to do so.
I don't want to frighten you, but most likely you bought a stolen phone.
The security in that phone is so good, nobody, till now has broken this.