Mobile Phone Under 25000

highly recommended RedMi Note 3

u have to buy oneplus two best phone in under 25 with 64 gb internal storage
and also 4k and slo-mo camera

I would personally like to recommend the OnePlus One Sandstone black, it is the best and affordable flagship phone ever launched, look on AnTuTu Benchmarks, it is in tge leaderboard and yet so affordable.

Yes exactly, you may don't find Nexus 5 better because of battery issue, but the smartphone could be better than Xperia Z1. I do find some users who aren't much happy with focus of camera of Nexus 5. But when it comes to the comparison of both these smartphones then Nexus 5 has come out as the best selection for many users. Reason, as @Sahil said, you get latest software updates with Google products. Design is also really cool. In my opinion, if you play heavy games then any smartphone's battery will die quickly. Battery doesn't seem to be the reason for not selecting Nexus 5.
Other smartphones are also differentiated with Nexus 5 here - http://gadgets.ndtv.com/htc-desire-820-1945-vs-lg-google-nexus-5-1115-vs-samsung-galaxy-note-3-neo-1256-vs-motorola-moto-x-gen-2-1962

The only issue with Nexus 5 is the battery. It will hardly last the entire day and more than often you will find yourself plugging it in for charging by mid of the day. Its otherwise a fantastic phone which will continue to get updates first for at least next 2 years, is snappy and will remain that way. If you restricted by choice between these 2 handsets, the Nexus 5 is the ONE

@Anant1 You have several options-
1.Nexus 5
2.MotoX(1 gen)
3.MotoX(2 gen)
4.One plus one

But I have read on the internet that the battery of Xperia Z1 is better than that of Nexus 5. It's camera is also better and it's waterproof also. But I'm still confused because the design of Nexus 5 is better than Z1 and well... it's Nexus!

Thanks for the suggestion but I don't completely trust companies like Gionee. So..

You should go for LG Google Nexus 5 without any doubt. The smartphone will surely solve your purpose if your budget is under Rs.25000. The one obvious reason is software updates that Google provide every time. The smartphone was actually released with Jellybean version but recently got Lollipop OS just after Android One smartphones.
Your other choice Xperia Z1 is also good. Sony smartphones are better known for their strong build quality. But Nexus 5 can fulfill all your requirements, be it a design, performance or else.

Go for Nexus 5!

You can try with Gionee Elife S5.5 smartphone. This is available under 25k and handy with 5 inch display. S5.5 is launched in July 2014 and available online.

Thank you for your reply. I was also considering Desire 826 but it has a huge screen which would be very big for me.
And as far as One Plus One is concerned, as this is a new company, I don't really trust it. And it doesn't have any service centres.
And Moto X (2nd Gen) is out of my budget. And 1st Gen is not in stock on Flipkart.

Neither! Both are old generation phones which are on their way out. Why would you want to put your hard earned 25k (remember its not a small amount by any means) in an obsolete mobile? I think you should consider following:
1. HTC 826 (with Full HD screen which was recently launched)
2. One Plus One - Now available without invites which is a huge advantage.
3. Moto X (but this would mean overshooting your budget)

I won't suggest anything from Xiomi, Lenevo, LG, Samsung as they are either not value for money or their UIs are gimmicky and they don't last long.