Sony Xperia Z3 Red Underline Spell Checker
I love my Z3 but the one thing that was missing was the red underline spell checker. I hate the suggestion feature. I had the red underline on my Note 2 (stock and Cyanogenmod) as well a my Nexus 7 (stock).
Apparently that feature is available in the Google Keyboard. But you can't install the Google Keyboard as it claims it's not available in this country :wtf:.
To get it back I did the following (after several Google searches).
This will only work if you have another device with Google Keyboard already installed like a Nexus 7, already assigned to your Google account. Alternatively, you could just get the .apk, seems it's all over the net (though I don't like this approach).
On my Nexus 7 update the Google Keyboard app via the Play Store. The reason for this is on my Z3 the Google Keyboard app can't be installed, the Play Store claims it is not available for my country :wtf:. By updating it on my Nexus 7, where it was already installed as part of the OS, it became available on my other devices' Play Stores under My apps/All. On the Z3 don't tap the app in My apps/All or else it shows the details where it says it's not available. Do a long press of the app in My apps/All and select install. After installing go to Settings/Language & input and make the Google Keyboard the default. Also enable the Spell checker. I personally disable the suggestions. At this point the red line spell checker still doesn't work. You need to restart your device.
Yay!
Also, to fit the Z3 style, in Google Keyboard Settings/Appearance & layouts/Theme select Material Light. (Holo White is black for some reason.)
Edit: there is no SA English in the Google Keyboard and I was set to SA English. This may be why it wasn't available in the store. UK English is available, so by setting that as your language may (or not) make it available