Could of been 5 Stars I have found the hammerhead Karoo 2 once you know how to use it after my garmin 520 an excellent bike computer. The mapping is outstanding and the data you can have on the screen is also very good. Its easy to use and you don’t need to change the mount from your garmin mount as an attachment comes in the box. The display is very clear and easy to follow. BUT I can’t give five stars as the battery life is very poor if you have a number of sensor going at the same time as the mapping. After a 2.30 hour ride I was down to 65% battery life. Come the summer am hoping this will last the 100+ miles a ride. I do think hammerhead need to look at this very quickly to compete with the likes of garmin. HOWEVER saying that I would recommend this bike computer as I am more than happy with it.

Fed up with workarounds The unit has multiple shortcomings but I guess these may be different for what you are using it for. I test the basics against an old but super reliable and functional Lezyne Mega C. It sends a live tracking email - Karoo can’t. You have to text a weblink. Lezyne permits a cadence (only) Bluetooth link but Karoo can’t - it takes speed and distance bundled with cadence and then conflicts with its own speed and distance measures - so speed and distance stop at random intervals and gives erroneous data. Lezyne displays a simple clear graphic of the SRAM shifter position. Karoo displays numbers… Lezyne is inexpensive and ‘just works’ Karoo 2 is expensive and needs constant tinkering or workarounds for you to try to justify the costs. Unfortunately I was well through my 45 days when I acquired my new modern ebike with lots of Bluetooth and Ant+ sensors. I have to unpair these to get any sense from Karoo 2. Am just wearied with it…

Never arrived, logistics nightmare I was not able to test the device as never arrived. Their logistic is a disaster. They sent a message that the device was sent and then they tell they cannot deliver, with any explanation. So I sit and wait for a parcel that never arrives. Sort out your logistics use a company like Amazon that knows how to ship goods.

Karoo 2 Explore with ease with the Karoo 2, and upload workouts from TrainingPeaks. No more stopping and more time riding.

Amazing computer, amazing company I've always disliked Garmin EDGE computers, but until the last few years there weren't many genuine alternatives. I've had several Garmin computers - 500, 510, 705, 1000 - all of them were buggy, had a poor user interface, slow to operate, and had issues with Garmin Connect. I tried a couple of times to ditch Garmin. I had a Polar v650 which was nice, but bricked when passing the military base in Mallorca. I also had a Bryton, but it had an even worse UI than Garmin, and didn't like rain. Most recently, I've had a Wahoo ELEMNT, which is a fantastic alternative to Garmin's EDGE computers. Last year though, despite being an advocate of iOS and Apple products, I plumped for Hammerhead's Android based Karoo 2 head unit. Hammerhead pay nearly as much attention to their packaging design as Apple - the boxes are well designed, and unboxing is part of the experience of ownership. Unlike Garmin, there's cheap looking printed glossy external boxes with fluted brown internal sections - everything is matt board with spot UV logos. It all feels very premium. Which is should do given the cost of the device. The Karoo 2 itself feels more like a premium mobile phone than a GPS bike computer. The plastics are high quality, everything is nice and tactile - a bit like a Wahoo ELEMNT in that instance. The screen display is bright and crisp, and it's easy to read everything even with my ageing eyes. As a UI/UX designer, I'm always picky when it comes to human/computer interfaces. I am easily frustrated by some of the poor UI design that we all experience on a daily basis, so any new bike computer has its work cut out to impress me. This is where the Karoo 2 excels over the competition. They've paid attention to the UX/UI design, the interactions are smooth and well thought out, and it is a breeze to use. As I say, it's built on Android, so unfortunately there are some obvious Android system screens in there but it's a small price to pay. Rather than building their own OS, Hammerhead have used a proven platform to build on so they can concentrate on their cycling specific features. The other thing about Hammerhead is they run their software side like a proper software company, and seem to adhere to Agile methodology. The release new updates often, and continually improve the features, functionality, usability, and interface of their product. I didn't ride outside over the winter (I have asthma and it makes it difficult for me) so I didn't use my Hammerhead from September until April. Turning it on in April there were updates to run, and there were multiple new features and updates added. I also experienced their customer service when my mount snapped. I contacted their support team, and within 2 working days I had a new mount free of charge under warranty. Ultimately, the Karoo 2 may not have certain features that Garmin users have, as Garmin is a more mature company. However, Hammerhead clearly have a backlog in place as they regularly update their firmware, and you can request new features and report bugs via their various support systems. One of the features I wanted was a climber function, and sure enough they have released one. If the Hammerhead has the features you need to use, then I'd seriously recommend ditching whatever you have now and going for a Karoo 2. Great computers, great software, great customer service.