Download the free Simba Sleep App and start tracking - that's pretty much it! Starting from July 22nd, we'll unlock a new #TryFor8 video with your weekly challenge and guided tips. If you only discover #TryFor8 half way through, it doesn't matter - you can start from week one whenever you like. And as long as you track any seven days (not necessarily one after the other) by September 22nd, you'll receive your voucher and draw entry.

On average, adults need five complete sleep cycles every night to get a fully restorative night's sleep, which takes 7-9 hours. Each cycle lasts an average of 90 minutes, and they're progressive - you get a different balance of deep, non-REM and dreaming, REM sleep from each one, so you need to get all of them to be thoroughly rested. Although five sets of 90 minutes is 7.5 hours, you should factor in some extra time in bed to drop off and wake up gently, plus the exact length of each individual's sleep cycles will vary a little. So trying for 8 hours in bed works for pretty much everyone - and after a few weeks of tracking and optimising your sleep routine you'll be able to work out more precisely where your sleep sweet spot is.

Ideally, every adult should aim to get their sleep cycles in every night, and trying for 8 hours in bed is a great way to acheive that. But we know that life can get in the way, and that there are lots of reasons, from waking with little ones to long work shifts that could affect your sleep. We'd still encourage you to make the changes you can to get the best quality sleep during your available rest hours. If you can, and you feel like it helps you, try fitting in a quality nap, too. Plus, as long as you track the hours you can get at least seven times, you're still eligible for your discount voucher and draw entry.

#TryFor8 launches on July 22nd, at which point you'll be able to update your app and it will appear on the main navigation. If it's past the start date and you still can't see it there, please head to the iOS App Store and update your app.

Absolutely. Any seven nights of tracking before September 22nd qualify. Do try getting in the nightly tracking habit, though - the more info you have about how your sleep habits are playing out night after night, the more you'll see how important sleep is in your daily life.

The Simba Sleep App measures your sleep duration and quality using audio, which is why it needs access to your microphone. It picks up breathing and movement and uses these to accurately assess whether you're asleep or awake and which stage of sleep you're in. It does also work with an Apple Watch if you have one and are happy to wear it while you sleep. As long as your phone is placed on the correct side of your bed, it's no problem if you're sleeping next to a partner, and you can each have your own independent tracking going.

And don't worry: all of this happens on your phone in real time. So as soon as the sound has been analysed in the moment, it's deleted. All your data is recorded locally, and no sound files are ever uploaded to us - they stay safe and sound on your device. You can download your own sleep data as a CSV file and you can also erase all data from the app (as well as anything saved to your iCloud). We can't and don't listen in; our tech does the analysis, and all we ever see are totally anonymous numbers.

Not at all - it's always a good time to #TryFor8! The challenges do start out at 'amateur' level and gently progress up to 'professional' status, so it's best to start from the beginning no matter how many weeks are already unlocked. The #TryFor8 challenges will stay on the app after they've all unlocked, so you can keep going. To qualify for your discount and draw entry, just track any seven nights (consecutively or not) before September 22nd.

We're always happy to help (except when we're doing our own tracking). Just drop us a line here: https://help.simbasleep.com/hc/en-us.