Within an hour or two of using the Oppo R5, you realise that there is a sort of singularity of purpose to it. When Oppo set out to build the R5, it wasn't going to make a phone that would dazzle the world with a super-powerful processor or some never-seen-before features. It was, quite simply, going to build the thinnest smartphone the world has ever seen. And, it did. At 4.85mm, the R5 did become the slimmest of its kind.Then something named the Vivo X5Max came by, and walked all over the R5's party.So, the R5 has now been pushed to second place in the slimmest phones list. Still, it is what it was supposed to be\: a fashionable, good-looking smartphone.Let's start with what's likeable. The R5's metal unibody, surrounded by a chamfered stainless steel frame, lends it an incredibly solid, premium feel. Despite being so thin, it doesn't feel fragile. It's an expensive handset, and it feels it, too. The back is matt-finished, and makes it a little easier to grip the phone, With a glossy back, the super-slim phone would quite easily slip out of your grasp. Oppo also provides a translucent plastic cover for the phone, but that only makes it thicker, so you're better off without it.Colours on the 5.2-inch AMOLED screen are nice and warm, and readability outdoors is quite okay. The 423ppi pixel density means that viewing content on the phone is a joy, and overall, it's a very smooth unit.Primary snapping duties are handled by a 13-megapixel camera, and they're handled quite well. In optimum light, the R5 clicks some really sharp and detailed images. Aiding the primary cam is a forward-facing 5-megapixel unit that also does a very decent job.Oppo's custom UI, the ColorOS 2.0, is a unique take on the stock KitKat OS. The app drawer's been done away with, and Oppo's introduced its very own Theme store, which offers some cool options to choose from. It's a vibrant OS on the whole, but may not be to the tastes of those who prefer bone-stock Android.But, there are compromises. Compromises which are present simply because the phone had to be that slender. For starters, there's no headphone jack. There was no space to fit in a 3.5mm jack, and so, Oppo supplies an adaptor which connects your headphones to the phone. Now, the stock headset is pretty darn good, but, the problem is with the adaptor. It's a tiny thing, and you're likely to forget it at home, or worse, lose it, in which case you'll have to either buy a Bluetooth headset, or use the loudspeaker. Not impressed.The specs are okay, and the 1.5GHz, octa-core Snapdragon 615 processor is fairly powerful, but it lacks the sort of punch you'd expect from a phone this expensive. The benchmark test scores were a long way off the scores registered by devices available in the same segment. Gaming is decent, but the phone does lag at times. Also, when you play heavy-duty games, the phone tends to heat up a touch more than you'd like. You get 2 gigabytes of RAM, but storage is limited to 16GB - of which only 11-odd gigs are available to the user - and there's no memory card slot.And finally, the one real problem\: battery life. A wafer-thin phone can also accommodate a wafer-thin battery. A 2000mAh unit, in this case. It's just not good enough. Battery longevity has fluctuated wildly in the time we had the phone, and there was an instance where I had to charge it all the way up twice in a single day, and still be anxious about the battery lasting till I made it home. Yes, Oppo's VOOC mini flash charger does do a good job of giving it about 80 per cent charge in just 30 minutes, but the manner in which the battery bleeds charge, the phone needs it. If you buy one of these, and travel a fair bit, make sure you carry a battery pack. You'll need it.So, the R5, then. A fashion statement it most definitely is. But, at a price of Rs 29,990, it is very hard to recommend. For those who only need a phone that looks good, and performs decently, the R5 will make the cut. But if you're the practical sorts, it's not for you.