FLAGGING A PERSON TO MAKE THEM AWARE THAT YOU HAVE MENTIONED THEM IN YOUR POST
If you type an @ and start writing a persons Health Unlocked name you will see a drop box appear and you can scroll down to that name and select it. The more letters of their HU name you type the quicker it will be found. It will then notify them that you have mentioned them.
So for BobD on here it would be (type the @sign first) then BobD. Bob will now get an email notifying him that I have mentioned him. Notice how the name turns blue when it's done correctly and the @ sign has disappeared.
IF YOU'RE NOT SURE HOW TO SPELL A WORD
On a PC there is an easy spellcheck (must be a way on a mobile phone or iPad too - someone tell us here please) . If you're not sure how to spell something, write the word as best you can (it will have a red line under it if you haven't typed it correctly) and then right hand click with your mouse anywhere on it and it should list the word spelt correctly, drop down to it and the word you typed will be corrected. A word I'm often not sure of spelling is arrhythmia so I write it as best I can, see the red line underneath telling me it's wrong and follow the instructions I've listed above.
Hope this information is of some use. I'm certainly glad I know the spelling tip.