NEW YORK (TheStreet) -- The LG G3 is the world's first major 1440 x 2560 resolution smartphone, and it's LG's flagship. I also recommend an LG smartphone as being the best buy in the market today.

But these two are not the same.

Let's first deal with the LG G3. It's the first major flagship smartphone with 1440 x 2560 resolution, a big step up from the previous 1080 x 1920 flagships. And the company had just replaced the fully satisfactory 720 x 1280 phones that started hitting the market in the fall of 2011.

Physically, the LG G3 is simply too large to be comfortable to hold, and it is very slippery. It got knocked out of my hands twice in two weeks, as my elbow touched someone else walking down the sidewalk.

You could use a case, but then it would become even bigger. It is hard to recommend a phone that is simply too big and too slippery.

The big phone fits a big battery -- 3,000 mAh -- but I did not find that the battery life was particularly good. The large high-resolution screen eats up a lot of juice. That made the battery life barely average for an Android flagship smartphone.

The large high-resolution screen has the obvious benefit of being great for reading articles and watching videos. If you're sitting on the gym's cardio equipment, reading and viewing, this is the smartphone for you. It's one step closer to being a tablet.

As with its predecessor, the G2, the buttons are now on the back, in the middle, right below the camera lens. I like this placement a lot, and it's pretty much a necessity once the phone becomes this huge.

The CPU (computer processing unit) performance is excellent, thanks to the class-leading Qualcomm (QCOM) 801 Snapdragon, which is on par with other flagship smartphones from Samsung (SSNLF) , HTC and, I think, also now Sony (SNE) . This is to be expected, as all of their flagships have superb CPU performance.

LG's custom software experience has been hugely improved from its previous non-Nexus smartphones. It is now aesthetically pleasing for the first time, with appropriate soothing colors and an overall simplified look.

The two things I like the most about LG's implementation of Android are:

  1. The KnockON feature, which wakes up the screen by tapping twice on it with a reasonable degree of firmness. This is better than moving your fingers around to find the on/off button.
  2. The KnockCode security feature, which enables you to unlock the device by knocking four times in a certain pattern on the screen. This is a genius idea which I wish every smartphone had.

The KnockCode system has two main advantages:

  1. It's easier to perform for the user, because the "target areas" are much bigger than the numbers on a dial pad. This means you can do it while focusing your eyes on something else. You pretty much learn in a matter of minutes how to do this without looking at the phone.
  2. It's more secure to unlock when there are people around you who may be snooping to learn your four-digit PIN. They likely don't know exactly what's going on when you knock away at your code, because they don't see any numbers or much of anything else, for that matter. So they are probably assuming that there is no code and that you're just a little mad for tapping on a screen that doesn't show much anything.

Even if they see that you're tapping something, it may be more difficult to follow if you're double-tapping somewhere, and they don't see you go from one number to another. In other words, it's just harder for someone to see what you're doing.

Please, Google (GOOG) -- make this KnockCode functionality standard in the Nexus Android. Yes, it's really THAT good.

The other really good part of the LG software is that on this gigantic high-resolution screen, it fits more app icons than any other smartphone anywhere near its size. This helps a lot. It's better than LG's own Nexus 5, and it's certainly much better than Samsung's Galaxy S5.

On the bad news front, the notifications and settings are cluttered in comparison the Nexus. Perhaps it's Sprint's (S) fault, as the device I tested ran on Sprint, but it was difficult to keep the notification area cleared. LG's own Nexus 5 does not have this problem.

Speaking of Sprint, in my experience, I found that the signal strength was generally not as good as the other devices I was carrying, running on Verizon (VZ) , T-Mobile and AT&T (T) . That said, that doesn't affect my testing much, or my verdict.

So should you buy the LG G3? Perhaps, but only if you have huge hands or will use it with a grippy cover. You must be obsessed with having the highest-resolution screen.

There is a good case to be made that the LG G3 is, in an objective "on paper" way, the best smartphone in the world. It's the spec monster of the season, that's for sure.

Yet, in the end, my previous recommendation for the best smartphone in the world doesn't change. It's still an LG, but it's the Nexus 5 -- not this G3.

The LG Nexus 5 feels wonderful to hold with its steady rubbery grip. It comes with the aesthetically pleasing plain Nexus software. It gets its operating-systems updates the fastest of any Android device. Google sells it at what must be a subsidized price. What's there not to like?

As I see it, the only noticeable and important advantages of the G3 over the Nexus are:

  1. The KnockOn and KnockCode features, as they are truly great.
  2. A much better camera, with quicker and more secure focus.

It may be a somewhat tough call, but in my book the advantages of the Nexus outweigh the G3.

If previous years are any indication, the Nexus 5 is about to be replaced no later than November by a new and better model, but even in its current form, now over 10 months old, the LG Nexus 5 maintains my crown as the best smartphone money can buy.

At the time of submitting this article, the author was long Google.

This article is commentary by an independent contributor, separate from TheStreet's regular news coverage.