If you're unable to login to FaceTime and iMessage because the login process repeatedly loops, check the time settings. If the time is not set to automatically adjust (Settings > General > Date & Time > Set Automatically > On), you might find that the login sequence for both FaceTime and iMessage loops. Once you set the time to adjust automatically, all is back to normal.
[kirkmc adds: I've never had any problems, since I've always had that setting set to On. But I've found that a number of odd settings can affect logging into Apple services, so it's worth pointing out.]
Apparently, this occurs when memory on the iOS device gets too low; the solution is then to force-quit as many apps as possible. You do this by double-pressing the home button to show the application switcher, then tapping and holding an icon until they all wiggle. Tap on the "do not enter" buttons at the top-left of the icons to quit them. Press the home button again to close the application switcher.
Since I saw the above article last week, I haven't had the dimmed dictation button, so I haven't been able to test this. I'd been restarting my iPhone when this problem arose. If you've seen this problem, please post in the comments to say whether this solution works for you.
Siri's ability to access Wolfram Alpha lets you access a huge amount of interesting data by talking to an iOS device. One useful thing thing Siri can do for you is ask Wolfram Alpha to generate a very secure, random password.
To do this, invoke Siri, then say "Wolfram password," or "Wolfram Alpha password." This retrieves an 8-character random password, along with a list of a half-dozen others. You can also have Siri get longer passwords, if eight characters doesn't ring your bell. Say, "Wolfram 14-character password," for example.
The downside to this is that you can't copy this password, and once you've switched away from the Siri results, you can't get them back again. So you need to either type this password on a computer or other iOS device, or write it down. Either way, make sure you delete it, or store it in some sort of encrypted file.
If you have an iPad or iPhone, and a friend wants to check out a web site, or your child wants to play a game, you may not feel comfortable lending them the device, since they can access your email, bookmarks, contacts and other personal data.
There's a way to lend a device to someone, however, so they can only access the current app. Go to Settings > General > Accessibility, and scroll down to the Learning section and tap Guided Access. Turn this on, and enter a PIN. Go back to the Accessibility settings, and scroll all the way down: you'll see, in the Triple-click section, that Triple-click Home is set to Guided Access. (Unless you've already set something else for the Triple-click Home setting.)
Now, to lend your device to someone, open the app they're going to use, triple click the Home button, then tap on Start. (You can also set some options before allowing access; tap the Options button at the bottom of the screen.) When the user is finished, triple click the Home button again to exit Guided Access; you'll need to enter the PIN.
I've just moved from a country where I had unlimited (really) data on my iPhone contract to one where data plans are metered and expensive. So this recent article by David Chartier, on the Finer Things in Tech web site, comes at the right time. It points out the simple setting in iOS to turn off automatic loading of images in Mail. As with Mail on OS X, you can load images later, but you won't need to load them for every message, saving download time and bandwidth.
To change this setting, go to Settings > Mail, Contacts & Calendars, and toggle Load Remote Images to OFF. If you get an email with images, and want to see them, just tap on Load All Images in the message.
This setting would make more sense if it only affected image downloads when using cellular data. But it's an all-or-nothing choice, so even when you connect via Wi-Fi, you'll need to download images manually, if you use this setting.
Google has added Google Now to its Google Search app for iOS. This provides local traffic information, weather data and more. Unfortunately, this also keeps GPS on permanently on an iOS device, depleting its battery.
After installing the new Google Search app, I had noticed that my iPhone's Location Services icon was on permanently. I quit all apps that could be using GPS or location services, but it was still visible. I restarted the phone, and it was still visible. It turns out that it was Google Now, and I resolved the issue by deleting the Google Search app.
You can also just turn off Google Now, in the Google Search app's settings. (See this screenshot by Dave Hamilton.) If you want to use Google Now, be aware that it will drain your battery, and remember to turn it off when you don't need it.
I assume Google will update the app soon to fix this, but in the meantime, it's a good idea to be aware of this issue.
Update, June 1: As you can see below in the comments, a Google representative claimed that Google Now has no effect on iOS device battery life. Interestingly, this person posted the exact same content on dozens, perhaps hundreds of websites that were claiming this was in issue. The Loop published an article with a screenshot for a recent update, whose notes discuss improving battery life. But The Loop's Jim Dalrymple, in an update to the post, says he might be wrong.
If you reply to an email message in iOS, you normally wind up quoting the entire message you are replying to. Usually, all you want to reply to is a portion of the message.
By selecting that portion of the message in the received mail before replying, only that selection will be quoted, just as with OS X Mail app and most other computer-based email programs.
To do this, tap and hold on a word in the section of the email you want to quote. When the selection handles come up, drag them to select only that portion of the email you want to quote. Then tap on the arrow button to reply to the message.
[kirkmc adds: This is pretty basic, but there's no hint on the site, and I'd bet a lot of iOS users aren't aware of this.]
I'm giving one of my iPads to someone soon, and a recent TechHive article pointed out the easiest way to prepare an iOS device to give or sell to someone.
Go to General > Reset, then tap on Erase All Content and Settings. If you have a passcode set, you'll need to enter the passcode to continue. An Erase iPad dialog will inform you that this will erase all media and data, and reset all settings; tap on Erase. Another dialog will ask if you're really sure you want to do this. Again, tap on Erase.
The screen will go black with an Apple logo and a progress bar, then you'll see the iOS device's name (iPad, iPhone, iPod touch) and a slider. Slide the slider to begin setting up the iOS device as a new device.
The TechHive article also noted that you can use this process to wipe and restore an iOS device; at one point in the setup process, you'll see a choice to set up the device as a new one, or to restore from an iCloud or iTunes backup.
When the process has completed, you'll have an iOS device with the stock apps and settings.
Our sister publication, Macworld UK, published a neat hint on recently, showing how to have an iOS device read texts from iBooks. iOS has accessibility features that can perform text to speech, but you need to know the trick to get this to work in iBooks.
First, turn on text to speech: go to Settings > General > Accessibility, and set Speak Selection to On.
Next, in a book, switch to scroll mode (tap the aA icon, then tap Themes to get to this theme), you can select a word and drag the selection far ahead in the book. Then, in the menu that displays, tap on Speak.
You can use this technique to have text spoken in any document, and there is a limitation in iBooks, where you can't select all the text and have it spoken. Since selecting is annoying - having to drag the handle a very long way - you may find this troublesome, but if you really want to have a text spoken, this lets you do so, even in iBooks, which is read-only.