Working out just to work out isn't the best motivation, and since I'm a sucker for gadgets and new toys, here's a few of my all time favorites:
[Android, iPhone] The slew of workout apps is pretty bleak. They're overcomplicated, they give too many alert reminders, they're clunky, and they're not conducive to climbing exercises. Fitnotes is the first that I've consistently used every workout.
Fitnotes is a simple to-do checklist of exercises you create for each workout. You select exercises with weight/rep/time for each workout, which I do before getting to the gym. There's easily-accessible history of your weight/rep/time for when you forget which dumbbell you used for those lateral arm raises (which is pre-filled when you add the exercise based on your last workout). If there's no exercise already in its dictionary, you can easily add them. It takes a bit to enter all the climbing workouts like hangboard, levers, campus board, etc. but then it work flawlessly. Once you're at the gym, your workout is as simple as checking off what you've done with what weight!
It only works natively on the phone--there's no cloud support. I was dubious at first, but it's incredibly easy to export to Google Docs and import back in, and all your custom exercises are transferred.
[Android only] The most frustrating tool to find is a good interval timer for hangout and suspension trainer workouts. I've literally tried almost 15 apps. This app by far surpasses all others because it's so simple. It baffles me how all other apps are so complicated.
You can set prep time so you can start your timer, chalk up, and then start the workout, very easily specify how long each workout/rest time is (the +/- on each digit is SO much faster than scrolly selectors in other apps), and specify how many rounds and the rest between sets. So you can set up, for example, 5 supersets of 10x (7sec on / 3 sec off) with 3min rest between each set, in literally a few seconds. The countdown timer is utterly simple and shows how many sets and supersets are left.
I have to put a plug in that the developer is awesome. There was a bug with his app that I contacted him about and he emailed back and forth debugging with me for a few days. Worth the $2 for the ad-less version for sure!
Woss Suspension Trainer
I have a major issue with the price and branding of TRX. Their classic yellow and black nylon trainer starts at a staggering $200. I refused to buy one when I was browsing their app for exercise ideas and saw that they wanted more in-app purchase money to view their own workouts!
Enter Woss. It's a military and climbing company that has a huge selection of suspension trainers, all priced from $24 - $60, and all exceptionally made. They're simple and do their job. Just browse their offerings on Amazon--I've never seen a company whose products all get 4.8+ stars.
Woss's website is pretty much a mess. I think for most people, you're looking for the 3000 Equalizer, the closest TRX-like trainer with 1.5" nylon straps. For more advanced, look at the Hurricane, which has a pulley on 12mm rope that forces you to balance the weight on each handle. The pulley is removable and you can do an overhand knot on a bight to make it just like a TRX. The handles attach to the rope with a Prusik knot. Both have a washer stitched into the nylon anchor that you can put behind a door for indoor use.
I took the Woss trainer on our road trip and it's very easy to set up in campground or city park kids jungle gyms.
Wahoo heart rate monitor
Bluetooth-connected devices are another product that should be simple but are hard to find done right. The Wahoo Tickr heart rate monitors have a pretty faultless connection. That said, the whole workout-fitness-devices industry is still behind what it could be, but Wahoo is a start.
Wahoo has their own fitness app, or it connects directly to Strava so you don't need to import your heart rate separately. I use their own app when doing indoor workouts since Strava doesn't work when your location doesn't move. If you get the Tickr X, it has motion analytics for up/down, left/right, front/back motion while running, which has been useful for my knee rehab.