I managed to pick up an iPhone 5s yesterday and have been trying out its new features and enhancements. Here’s my review of the device after using it for 24 hours…

Design: As the name implies, the iPhone 5s is based directly on the design of the iPhone 5. It has the same shiny edges, metal back with glass top and bottom caps, and front that is dominated by the display. The only tell-tale signs that the 5s is not a 5 are the slightly tweaked Home button design, larger rear camera flash, and if you opt for one of the two new color options.

I chose the Space Gray version. Yes, I did not have much of a choice given the extreme constraints to the silver and gold options, but Space Gray is what I would have picked regardless. Why is it called Space Gray? Only Apple could answer that, but If I was in charge, I would have named it “Dark Silver.” The color is more in-line with the silver metal on the white model, but it is noticeably darker.

I’d say that the gray is akin to the metal band around the iPhone 4 and 4S, making me think of the Space Gray iPhone 5s design as being the best of both the iPhone 4 and iPhone 5. I really do enjoy the Space Gray model, and, from an aesthetics perspective, think it is much nicer than the black/slate iPhone 5 (which I carried previously).

In comparison to the iPhone 5’s black glass on the front and back, I think the 5s’s glass is slightly darker/less transparent, but this could just be my perspective.

The phone feels just as solid, thin, and light as the iPhone 5, so no shock in heft for customers coming off of an iPhone 5. But for those coming from an iPhone 4/4s or earlier, this design is a leap forward in construction and feel.

The leather case: To go with the iPhone, I purchased one of Apple’s new iPhone 5s leather cases. While in line, Apple employees passed around the new case in every color, and the stores seemed to have had ample supplies of the new accessory. Had this story been written about an iPhone launch in year’s past, I don’t think I would have been able to say that. I chose the black leather case to match the phone’s color, but I think the beige and Product RED versions are also impressive.

The case looks and smells like leather, but it does not have much heft or thickness to it. In fact, a Twitter user compared the feel of the case to an egg carton, and I would agree with that. The leather is definitely a different feel from the material used for the iPad Smart Covers. I do very much enjoy the case, though. It’s thin, light, and its design matches the phone well. I don’t normally use cases, but I think I am going to keep this one.

I also purchased the iPhone 5s dock, but the case does not fit in it. For a company that prides itself on completely integrated solutions, this is surprising to me, but not a true flaw. Removing the phone from the case is not difficult, but it requires effort.

I do recommend the case, but I think it is slightly overpriced at $39. The $10 difference between the leather case and the silicone iPhone 5c case makes sense, but perhaps the pricing should have been $19 and $29, respectively.

Battery life: I haven’t conducted extensive battery testing for the iPhone 5s, but I can say that it has slightly exceeded my expectations. I’ve been using the phone moderately (tweeting, texting, some web browsing, email, and a half-dozen or so phone calls) today, and I am at just under 70% battery life. Based on what I remember about my iPhone 5, this is solid battery performance. Of course, this could change as the battery continues to calibrate, and I did attempt to calibrate my battery yesterday by running it down to 0% and charging it up fully.

Performance: The iPhone 5s, so far, does not feel much snappier than the iPhone 5. This is not exactly a negative thing; the iPhone 5’s system speed is already fantastic. Moving around the operating system and launching apps mostly feels the same on the 5s as with the 5. I’ve done some unscientific measurements by launching the same apps simultaneously on both devices, but the results are always close.

For those coming from an iPhone 5, the speed increase will not be very noticeable for minor tasks. I remember when I upgraded from an iPhone 3G to iPhone 3GS, the speed increases were certainly visible to me throughout the system. Moving from the iPhone 5 to iPhone 5s does not take the same leap in my usage. However, those upgrading from anything below an iPhone 5 will be delighted. The speed difference between my A5-based iPad on iOS 7 and this iPhone 5s are night and day.

The new speed is slightly visible in terms of animations. For example, swiping through Home screens on the 5s feels ever-so-slightly smoother than on the 5. Moving between camera modes on the iPhone 5s is noticeably quicker than on the 5, and even swiping down to access system-search on the 5s’s Home screen is smoother than on the 5. Similarly smoother is swiping down the transparent Notification Center panel.

Another unscientific speed test I often like to test with phones is the speed of rotating an app interface. For example, rotating the Music app from portrait to landscape opens up a new “Album Wall” view, and changing the orientation of the Calculator app moves between a simple interface and a Scientific Calculator mode. So far, I’ve felt no difference here between the new phones.

I have also tested the speed of turning off and turning on the phones. The speed of booting down has been consistently the same, but booting up the device has been approximately 2-3 seconds quicker on the 5s. Both of these phones are running mostly the same content.

Another place where you will find a difference is in booting up graphically-heavy games. Games seem to load more quickly for me, but I have not fully tested gameplay in titles such as the new Infinity Blade.

I feel as if the iPhone 5s would seem even faster than the iPhone 5 if it were not for some of iOS 7’s lengthy animations. Animations that deal with length are mostly present with launching apps, closing apps, and unlocking the phone. Apple should decrease this glitz.

Speaker: With phones that play media like games, music, and video, the audio quality is important. The iPhone 5’s speaker sounds solid, and the 5s’s speaker sounds seems to have equal performance. An App Store decibel meter tells me that the 5s is literally a couple to a few decibels louder than the 5, but this is unscientific, casual testing.

Camera: I haven’t used or compared the camera much, but the speed of taking photos is clearly quicker on the 5s. Burst Mode works well and the user-interface for navigating between your several shots is simple.

Likewise with slow-motion mode, taking 120 frames-per-second video is fun, and the system for choosing which parts if your shot that you want to be slowed down is simple to use. A couple people tell me that they have had trouble playing back the slow-motion video via AirPlay on an Apple TV, but the results are not consistent.

The new True Tone dual-LED flash has made for noticeably better night-time photos. Control Center’s flashlight feature only lights up the top bulb, but I don’t consider this a flaw, just something I was curious about.

Touch ID: Unless you’re a camera enthusiast, Touch ID is the reason to upgrade from an iPhone 5. Of course, those coming from a non-iPhone or an iPhone older than the iPhone 5 will have plenty more to find new. Touch ID is simple to setup. Either during the iPhone’s setup process or in Settings, the iPhone can register your fingerprint. In the iPhone’s main setup mode, the process primarily focuses on registering one finger, but you can add up to five. I found the setup process simple to follow, and it took less than a minute for a single finger. Apple definitely nailed it with the setup software.

The hardware aspect of Touch ID has been terrific for me thus far. The system has recognized my assigned fingerprints nearly every time I have gone to unlock my phone. It is noticeably quicker than entering a four-digit PIN. My muscle memory is yet to fully adjust to not sliding to unlock, but I’m sure it will get there soon. I think Apple should make the slide to unlock screen less prominent on the 5s, but it is still (obviously) important to keep around. Unlocking the phone with my fingerprint has been a joy so far, and the hardware seems to be out of a different universe from fingerprint scanners that I have used on other devices. We’ll have to see, though, how that holds up after months of use.

While unlocking the phone has been mostly perfect, the general Touch ID system is not. I’ve had two main issues with Touch ID. The first revolves around scanning the fingerprints. Sometimes when clicking my Home button, I use the very tips of my fingers rather than the larger area where you main fingerprint is found. So unlocking the phone will not work for me with Touch ID in those cases. Perhaps I could have done a better job positioning my finger during the setup process, but I feel that the system should have given me the opportunity to add “more of my finger” to individual fingerprint registrations. I easily solved this issue by registering the tip of my thumb as a new finger, but this takes up one of my five slots.

My second issue with Touch ID is all about making purchases from the App Store, iTunes Store, and iBookstore. It works, and it works well, for simply choosing an item and downloading it. But I am very surprised that Touch ID was not more fleshed out for tasks involving Apple’s stores. For example, signing into iTunes Radio and iTunes Match required inputting my full password. As did trying to redeem an app on the App Store with a promo code and other occasions in which Apple would pop-up the Apple ID login screen. Until those gaps are filled, Touch ID is not a password replacement for Apple’s iOS media stores.

iOS 7.0 for iPhone 5s shipped with a well-documented bug involving Touch ID not consistently appearing as an option for authenticating downloads. I have not seen this issue while running the already-available iOS 7.0.1 update.

I feel that Touch ID could be even more attached to payments, such as in the Apple Store app and third-party apps, and Tim Cook seems to agree. There’s been a lot of talk about Touch ID, Apple storing your fingerprints, and security factors. I’ve disregarded all of that and I think it is a non-issue. Apple says that it does not store your fingerprints on its servers, and I have no reason to not believe that.

Conclusion: The iPhone 5s seems to be a great update for anyone upgrading from an iPhone 4s or older, for those getting their first smartphone, or for customers wanting to try out a different platform. For those moving from an iPhone 5, it is a bit of a tougher sell, but the promise of Touch ID and the future of 64-bit apps could be worth the excitement for some iPhone 5 users.