Working in tech support, I've come to discover that the people who never reboot their devices or better yet - never shut off their devices - are always the ones to complain about the following:
Slowness
Freezing
Wifi issues
Battery life
Rebooting when one experiences these issues is one thing. It doesn't justify shutting down your iPad every night and turning it on in the morning.
Doing this also masks the real issue: The solution isn't to just shut down your device every night, or even just rebooting when there's a problem. Those are just bandaids. The true solution is to find the app causing the issue, and either getting a patched version that fixes the problem, or finding an alternative app that does a better job at resource management.
Always. Then when you ask them the age old question "when's the last time you shut off the device or restarted it?" And they look at you like you have antlers growing from your forehead "no, why would I do that?"
This is a valid question. iOS is a mobile device OS, intended for long run times and use on limited resources. For the most part, save some memory management inefficiencies on Safari (which can be dealt with by quitting the app from time to time, if you're really having trouble), it's intended to be operational for days, weeks, months.
The old wives tale of "using too much power to shut it down" or "wearing out the components by turning the computer on and off" is rubbish and makes no sense; as well as having no actual research to back the claim.
And this is why people get bad tech support: issues of older technology are conflated with current tech, some old, outdated truths are mixed in with just plain bad advice, and then you get people who think they know it all, when they really don't.
Here's the truth: It IS correct that shut downs and startups don't induce mechanical wear. That
was the case on older desktop computers with spinning disk drives. But current disk drive tech has largely resolved this, and iOS devices (and pretty much every other smartphone and tablet) don't use hard disk drives at all. They use NAND Flash, which for all intents and purposes have no moving parts. So, starting up and shutting down an iPhone doesn't wear out the components mechanically.
The startup and shutdown process DOES, however, use power. Whether it uses more power than leaving it on at night in sleep mode is debatable. Given that
average annual cost to power an iPad is $1.36, it's probably safe to say that shutting down and powering up your iPad every night isn't really saving you much power or money.
The notion of regular reboots and shutdown/restarting to keep your computer fresh is a holdover from the days when Windows 95 and Windows 98 were the dominant operating systems. Win95/98 had notoriously bad memory management and their power management was deeply flawed and unreliable. Back in the late 1990s, yes, it made sense to shut down your computer when not in use because your system WOULD be more stable when fresh. But that pretty much went away when Windows XP came out, and never really has been an issue on *NIX-derived operating systems, of which iOS is one.
If that was the case, you would never stop your washer and dryer, dishwasher
Washers, dryers and dishwashers are different devices. They use hundreds, sometimes thousands of times more electricity than an iPad ever will. Washers, dryers and dishwashers also don't have a low power sleep mode state; they're either on or off. You also HAVE to turn off these devices from time to time if you want them to do their jobs, since they need to be loaded and unloaded. Most importantly, there is no point to keeping a dishwasher, washer or dryer on all the time when there's nothing to wash or dry.
By contrast: an iPad has a low power mode, uses way less power even when fully on, and there IS useful work being done when an iPad is in sleep mode: e-mail fetching, app updates, iCloud backups, and notification receipt.
- do you always keep your TV on?
Depends on the TV. Newer smart TVs have a lower power sleep mode and have apps that update in the background... in such cases it makes sense, just like an iPad, to keep it powered.
I think a more appropriate question is: Do you
UNPLUG your DVR when you're not watching TV? Or how about: if you have a landline phone, do you unplug that at night?
I've shut off my original iPad every night since I got it launch day. Apple just ran a diagnostic on it last week because my mother bought it in to them (as she owns it now) and they told her the battery was at 90% capacity - the Genius was shocked for a 4 year old battery.
Great for you. Though the reality is, it's possible to shut off an iPad every night and still have the battery wear out in less than a year. What matters are battery cycles and environmental conditions. If one really taxes the CPU and resources of an iPad during the day, they could expend more load cycles on a battery than the average, even if they shut down fully at night. At the same time, a light user could maintain good battery health over time, even if they keep their iPad powered on 24/7.
Also, you must've had one heck of a fluke battery, as lithium polymer and lithium ion batteries do degrade with age, regardless of use pattern. Even with minimal load cycles, 90% capacity over 4 years is largely unheard of.
There's no harm in doing it
You're right. But there's no
help in doing it, either. And you're interfering with background processes which could be done efficiently overnight while plugged in, that must now be done manually by the user when on battery and in use... which
uses more battery.
- in fact you may see more benefits than you can imagine
No, there's not much to imagine here, unless you're imagining fantasy.
TL;DR: If it really helps you sleep better at night to shut down your iPad every night, go right ahead. But the reality is, it's truly no better or worse than leaving it on all the time.
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Has not Apple given any official recommendation on this matter?
Nope, because it doesn't matter either way. Though, it goes without saying that an iPhone is completely useless when turned off (since you know, it's supposed to receive calls and text messages and stuff). And the iPad's OS is largely modeled after the phone.