Since I’ve owned an iPhone, updating to a new major iOS release has always been an enthusiastic and impulsive “Let’s update right away” process. With iOS 7, however, I started having some doubts. Not because of its new features and radically new look (I actually loved the new iOS 7 aesthetics since it was previewed at the WWDC). My concerns were more hardware-related: what if the single-core A4 processor of my iPhone 4 couldn’t keep up with iOS 7 general demands, resulting in a worsened performance, in turn making me regret updating in the first place?

So I started searching around the Web and asking other fellow iPhone 4 owners on Twitter and App.Net whether they had updated to iOS 7 and what were their impressions. I had some generally reassuring responses, the mandatory “Your Mileage May Vary” disclaimer, then someone pointed me to this article on ArsTechnica: New Lease on Life or Death Sentence? iOS 7 on the iPhone 4. It is a very interesting read, both the article and the comments. I usually ignore comments on these big tech sites, but in this case I wanted to read as many reactions as possible before venturing to update my iPhone 4, or deciding against it.

The article is well written and informed, and explains in detail what iPhone 4 owners get and don’t get in term of iOS 7 features, shows the differences in the graphical rendering of translucency effects (simplified for the iPhone 4), and goes as far as detailing the difference in launch times of a series of frequently used apps under iOS 7 versus iOS 6. The gist of the article is that iOS 7 feels slower than iOS 6: apps take longer to load, and:

[…] the A4 struggles to render iOS 7’s sweeping new animations consistently. I’ll repeat what I said in the iOS 7 review: iOS devices (especially the oldest ones) have always been capable of occasional stuttering, but iOS 7 magnifies these issues by using more animations and by making those animations more sweeping and longer in duration. More animations means more opportunities for stutter, and longer animations means that this stuttering is much more noticeable when it happens.

Battery performance is “down a little, not a lot,” and the final advice is to proceed with caution.

As you can imagine, after reading this, my instant reaction was OK, I’ll stick with iOS 6.1.3, thanks. Reading the comments, I found a surprising range of reactions, going from Everything’s sluggish and a mess to Performance is not bad at all, no problems here (I’m paraphrasing). At this point I was feeling more confused… and intrigued. Someone suggested that a good idea was to restore the iPhone before updating and set it up as a new device, so as to get rid of all the caches and rubbish accumulated up to iOS 6. Another reader reported that on his iPhone 4, performance under iOS 7 wasn’t much different from iOS 6. Another warned that typing on the virtual keyboard in iOS 7 was painfully, annoyingly slow. And so on and so forth.

After a while, I was considering to approach the update like this: grab the 6.1.3 firmware before Apple invalidated it, restore my iPhone to factory settings, update to iOS 7 and, in case things turned up to be disappointing, I could attempt a downgrade. Then the idea of setting up the iPhone as a new device, and configuring again all my preferences and each app’s settings, didn’t sound all that appealing. (Restoring from a previous backup after setting up the phone as a new device, in this instance, isn’t a bright idea, as you’d be reimporting the rubbish you wanted to get rid by doing the Restore). So, at the last minute, I decided to simply update the iPhone leaving everything in its place, and hope for the best, the downgrade to iOS 6.1.3 always being my backup plan, so to speak.

Actually, I was forced to do some cleaning before attempting the update, because it seems that iOS 7 needs 3.3 GB available on the device during the update process. I have a 16 GB iPhone, and there were only 1.9 GB available before updating. I moved some photos, cleared caches in apps like Spotify and Flipboard, emptied or reduced the photo libraries inside apps like Hipstamatic, Camera+ and VSCO Cam, which, if you don’t check periodically, can become rather sizeable (you can see how much space apps take up by going to Settings > General > Usage). I also trimmed my Music library, leaving only essential things of my collection that I can’t find on Spotify. When I got to having 3.55 GB of available space, I proceeded with the update. I chose to do it the wired way, via iTunes, instead of over the air, simply because it was more convenient at the time.

Now, I had read some comments saying that the update process on the iPhone 4 “took forever”. I don’t know what their idea of ‘forever’ is. Downloading iOS 7 was rather slow, so I left iTunes doing its thing in the background until the download was complete. The installation process itself took 24 minutes, which is not that much, all in all.

I’m reserving my observations on iOS 7 for a separate article. What follows are initial impressions specifically related to iOS 7’s performance on the iPhone 4:

• Animations and springboard navigation — The very first reaction as soon as I was able to see iOS 7 in action was that it’s faster than what I was led to believe. Animations are acceptable and, so far, I haven’t seen any noticeable stuttering or lack of fluidity. Some animations and transitions are different from iOS 6, so I feel the experience as being different rather than disappointingly slower, if you know what I mean. Flipping through the various screens is pretty much the same as in iOS 6. The animation when bringing up Notification Centre and Control Centre looks smooth enough. Same goes for the new multitasking management interface. Overall, browsing the iPhone 4 under iOS 7 doesn’t feel slower than before and the general performance is better than anticipated.
• The virtual keyboard — Contrary to some comments I saw on the ArsTechnica article, in my quick tests there is no noticeable delay when typing with the virtual keyboard. One curious exception: there is a longer delay when pressing the 123 / ABC button to switch from letters to numbers (and vice-versa). Fast typists will likely be annoyed. I’m not particularly fast with the iPhone keyboard and this delay is just a minor peeve for me. I’ve been told over Twitter that the keyboard delay may vary according to which app you’re typing in, but so far my experience has been rather consistent after trying Messages, Mail, Safari, Chrome, Spotlight, Google Maps, Mailbox, Twitterrific, Felix for App.Net, Netbot, the Merriam-Webster Dictionary, eBay and other apps.
• Battery life — It doesn’t seem to be worse than before. The only precise piece of information I can offer is that battery was at 92% just after updating, and was at 77% after five hours of moderate-intense usage. Which doesn’t look bad at all. This is just a feeling, so don’t read much into it, but since updating to iOS 7, it seems that the iPhone has a better battery management while in standby. With iOS 6, sometimes I would notice unusual drops in battery percentage even after a few hours where the iPhone had been lying around unused. With iOS 7, I still have to notice the same phenomenon.
• Camera and photography apps — I take a lot of pictures with my iPhone, and one of the things I feared before updating to iOS 7 was ending up with a slower camera experience. I don’t mind if Safari takes one second more to launch, but I do mind if the Camera app does. Fortunately, I discovered that there’s no worsening in Camera performance under iOS 7. Occasionally (the behaviour is not reproducible, though), the Camera app took a fraction of a second more to launch, but a good thing I noticed is that — once you’re in the app — the shutter feels snappier and slightly more responsive than with iOS 6. Other photography apps I often use, such as VSCO Cam, Hipstamatic, KitCam, Camera+, Hueless and Mattebox, seem to offer the same performance they did before under iOS 6. And that’s been a relief for me.

Overall, and citing the ArsTechnica piece, I’d say that iOS 7 feels more like a ‘New lease on life’ rather than a ‘Death sentence’ for my iPhone 4. The general performance is surprisingly good considering the aging hardware, and not disappointing compared to the situation under iOS 6. At least for how I use my phone. If you fiddle constantly with your iPhone, you may find certain transitions (lock screen to home screen, going in and out of apps, etc.) to be slower than before. I find them more pleasing and less ‘harsh’, but that’s me. I can safely say I’m glad I decided to update and don’t regret doing so. 

I may update this article in the following days, adding new observations, discoveries and things I may have forgotten. If you have specific questions about iOS 7 on the iPhone 4 or issues you want me to cover, write me an email (my address is at the bottom of the page), or drop me a line over at Twitter (@morrick) or App.Net (@morrick).