It's a little hard to know what to say  about the HTC One M9, the Taiwanese company's latest flagship smartphone. The phone is already up for pre-order — $650 for an unlocked version — and will hit stores April 10. And there are few criticisms to make: Inside and out, this is a solid phone, and one that can probably carry the line's reputation as one of the best Android smartphones out there.

And yet, if anyone asked me why they should pick this phone over its competitors — namely the Samsung Galaxy S6, which comes out on the same day — I'd be at a loss for words. In fact, even if you asked me if this was a necessary upgrade from last year's model, I'd ask what else was going on in your budget before answering.

Which isn't to say that there isn't a lot to praise about the One M9 — even if that praise is a little bit faint. Those who like the HTC One M8 will find a lot to love, including an improved camera, the same great front-facing speakers and elegant construction. HTC's definitely decided not to change a winning formula here, and has even added some polish. The company's changed small, thoughtful things such as the position of the power button — now on the side rather than on the top — to make it easier to hit the button when gripping the 5-inch device with one hand.

It performs just fine in the course of regular use, though it can lag on occasion when photo-editing or showing high-quality video — surprising, given its powerful Snapdragon 810 processor and 3GB of RAM. Battery life is also strong, with the phone getting through a full day's use on a single charge and even stretching another half-day in the course of my testing.  (Some reports have noted that the M9 runs a bit hot; that's not a problem I experienced in my week with the phone.)

HTC has also made some tweaks to the phone's camera, giving it a 20 MP sensor that performs well, though is still a bit fuzzy in low light. You can also take a picture with two cameras at once, and blend your two shots.  Overall, though, it should fit the needs of most users. The phone also comes pre-packed with HTC photo-editing software, which lets you drop in cool effects on your pictures, such as the ability to add in a kaleidoscope effect.

If you buy this phone, you will like it. But here's the thing: There's no feature that screams "Buy this phone!" And that's a problem for HTC, and for consumers who are looking for a specific reason to buy this phone over its competitors.

It doesn't have a fingerprint reader, or come linked to any useful services such as those for payment, for music or for extra cloud storage. (Though it does come with a promise for a one-time replacement if you drop the phone, called "Uh-Oh Protection.")  It doesn't have built-in waterproofing or even a gimmicky feature like a built-in game control pad.

Basically it's a good phone, maybe even a great one, that just doesn't stand out from the pack. That makes it hard to recommend it to any specific audience — particularly one already mostly locked into Apple or Samsung's universe.