Hello abhinav,
I was in the same shoe as yours few months back and had to take this decision.
I have not experienced byju first hand but really not heard good about them.
I would advice you to use recommended stuff for GMAT basics. Manhattans books are available and I think will make excellent reading for basics.
If u want video lessons then veritas has its entire course( I mean it) for free as an app both on android and iOS.
Finally when u have to do questions... The best thing is official GMAT practice tests , and gmatclub quant is amongst the best. For verbal try the egmat trial account.
Don't rush into spending money on anything not useful because u would ultimately be wasting time on them as well.
If there is anything else I can help u with I will be glad to help.
Thanks
Manish
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