I've been around long enough to remember handwriting recognition's checkered past.

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Back in the mid 90s, for instance, Apple introduced its (now-long-defunct) Newton handheld device. It was a cool idea, but the handwriting recognition was an epic fail.

As part of a Newton review, I tried writing lots of goofy words on the device's screen with my finger, to see how it interpreted them. One example: the Newton translated "Pia Zadora," the name of an obscure singer-actress, into "pig radar."

Twenty years later, handwriting recognition has returned to Apple handheld devices, this time in the form of the free third-party keyboard MyScript Stack. Apple recently opened up iOS 8 devices to non-Apple keyboards, so you can scribble words, one character at a time, using an input panel in various apps across your iPhone or iPad. It's sort of like using a Palm Pilot again. If you don't remember Palm Pilots, they were a post-Newton device that actually had decent handwriting recognition technology.

In my tests, MyScript Stack worked well, after some trial and error. Will it replace SwiftKey or Apple's own keyboard as my go-to input method? I doubt it.

After many years as an iOS device user, I've grown accustomed to Apple's keyboard, imperfect as it may be. With iOS 8, the Apple keyboard (finally) caught up with Android keyboards when comes to predicting words you're typing.

But there's something else to consider: security and privacy.

Both SwiftKey and MyScript Stack want you to give them "Full Access" to whatever you type using their keyboards. The screenshot below shows the permissions this Full Access gives developers.

Here's Apple's statement regarding third-party keyboards and privacy:

"If you enable Full Access, developers are permitted to access, collect and transmit the data you type. In addition, if the third party application containing the keyboard has your permission to access location, photos, or other personal data, the keyboard can also collect and transmit that information to the keyboard developer's servers."

Developers say they want full access to what you type so they can learn from your word-usage patterns and provide more customization options, which seems reasonable, to a degree. I probably wouldn't use a keyboard like MyScript Stack to input credit card numbers or other highly sensitive information anyway.

Still, there's something about this "full access" thing that feels a tad unsettling. Until (or unless) I get over those qualms, I won't be using any third-party iOS 8 keyboards on a regular basis, no matter how well they work.

If you're comfortable with the idea, MyScript Stack could save you time and aggravation. It even got "Pia Zadora" right.