Best for hardcore headphone wearers: Aaptiv
Finishing a workout is hard enough without the temptation to take an Instagram break every 30 seconds. Banish your smartphone screen's seductive powers with Aaptiv's audio workouts: simply pick your fitness goal, select a trainer, stick your headphones on and get sweaty.
Much more than an encouraging voice in your ear, the app offers hundreds of guided workouts (from yoga to running to crunches) alongside goal-specific programs. Aaptiv even handles the playlist, so there's no excuse for quitting after the first round to 'mix up the beats'.
Best for time-poor quitters: 30 Day Fitness Challenge
Don't have time to get sweaty every day? 30 Day Fitness Challenge begs to differ: whether you're a city slicker dashing for the Tube or a welly-wearing sort hurrying out to the cows, the app will nudge you to squeeze in a brief but meaningful workout every single day.
There are three difficulty levels and you can opt to work on your abs, bum or whole body. Intensity increases as you progress – but you're so busy you probably won't notice, right?
Best for egotists: Carrot Fit
“Hi, chubby human.” So begins your relationship with CARROT: a sadistic robo-trainer whose approach to motivation is a heady mix of ridicule and scathing sarcasm.
As rotund animations bounce around on screen, you’re expected to survive the ‘7 minutes in Hell’ workout in order to “science your lazy carcass into a form more consistent with what celebrity magazines say you should look like”.
Glutton for punishment? As the savage AI has insults you into shape, she can also judge your calorie intake in CARROT Hunger.
Best for form fanatics: Kaia Perfect Squat Challenge
A squat’s a squat, right? Wrong! Shoulders back, arms out, core engaged: it might be the best bodyweight move out there, but there’s a whole lot to get wrong with the humble squat.
Fling this app at your iPhone and it’ll use AI to track 16 points on your body, before comparing your form to that of the ideal squat. Simply prop it on a table, step seven feet away from the camera and drop down low. Sadly, it can’t help you get back up.
Best for heavy lifters: Strong
Remember how your friends used to come and count reps for you? Alas, the grunting, groaning and gurning proved just too much for them to face.
Ditch the quitters and make Strong your new gym buddy: from exercise instructions and warm-up calculators to custom routines and an all-important rest time countdown, it'll make you wonder why you ever invited the pub crew into your 'zone of gains'.