The fitbit Charge is a funny product in as much as I have a love-loath relationship with it. I love the fact that it monitors my movement during the day and at night, but I loath the build quality. I'm writing this review after 18 months of ownership.First lets talk about the good stuff.Most of this is to do with the app and applies to all Fitbit trackers, not just the Charge.I'll start with the hardware side first tho.The charger is small and easy to use. It would be nice if they supplied a slightly longer cable as it can come loose or be easily knocked out.The battery is good. I get a good week between charges and only take it off when I shower.The display is clear and easy to read.The vibrating alarm is a revelation and the way I now wake up in the morning. It's great. I don't wake my wife and there's no risk of waking the baby either! Brilliant!The step tracking is great. These things will never be 100% accurate, but it's good to know roughly how many steps you've taken in a day, especially when you sit at a desk all day. It gives a good idea of how active you've been and you can compare day to day. It's often this caparison that is more important than the actual numbers.The hourly activity tracker is also particularly good especially when working at a desk as it encourages you to get up and move when you can. A recent article in a broadsheet newspaper (I can't remember which) compared the effects of sitting at a desk all day to being the same as smoking! Apparently it's entirely reversible however by exercising for an hour a day. So, this is an ideal way to keep track of how you're doing.The sleep tracking is also very interesting. It's not entirely accurate and I'd like to see some more sensitivity settings, but it gives you a good idea of the quality of your sleep. Like the steps it's better used as a comparison of one night to another than as an actual indication of a particular night.The badges and goals give you a nice lift, especially when you start using it. It's nice to be praised on a semi-regular basis. These become less frequent the longer you have your fitbit, but by then using your fitbit is habit and you don't need the encouragement as much. Still nice to be told you've walked the length of the Sahara desert tho!Challenges are pretty motivating and can lead to hysteria among your friends if you let it. As long as you have a group of friends or colleagues who use a Fitbit too you can have daily, weekly or weekend challenges for highest step count. Just beware of your friends with short legs who take twice as many steps to cover the same ground! ;)The integration with 3rd party apps is really good. More below.Things I don't use, or use less frequently:I don't use the water intake monitor. I just can't see the benefit personally.I don't use the food planner/diary. The food items are geared more to a US market (or at least they were when I first bought my fitbit), but you can sync it with MyFitnessPal which has a much better catalogue of foods and allows you to scan barcodes with your phones camera (which works really well). I did that for a while when losing a bit of weight, but stopped. You can also use MyFitnessPal to sync workouts too. More below.I don't use the workout tracking on the device itself (press and hold the button). I found that it was difficult to do that and use the apps that I'm already using to track my running. In the end The app I currently use (RunDouble) doesn't sync with Fitbit, but it does with MyFitnessPal. I therefore sync RunDouble to MyFitnessPal and then MyFitnessPal to Fitbit. It sounds like a bit of a chore, but it works really well.I do use the weight tracker to keep a log of my weight a couple of times a week, but I don't use it for a weight goal. I imagine that like the other badges it would be a really good way of motivating weight loss however.The flights of stairs climbed is novel at best. It actually tracks changes in altitude and when I finish my normal running route it thinks I've climbed 15 flights of stairs despite not going near one. So take from it what you will.The distance is based on your stride length that you enter in the app and takes a bit of getting right. My advice is to walk a set reasonable distance (1k or greater) and then divide it by the number of steps you've done to get a reasonably accurate stride. You can do this for walking and running strides. Because I don't use the workout mode the distance is generally less than it should be on running days. I've accepted this as a fact but you can still use it to compare one day to another, it's just not accurate.Now the bad...The call notifications just don't work with my Android phone and fitbit. My fitbit tells me I have a call and who it's from, but a long time after the phone started ringing and often after I've picked up or they've hung-up. I think it's better on an iPhone, but I don't know an Android owner for whom it works.Most importantly, THE BUILD QUALITY IS AWFUL! I know that seems a bit dramatic, but it's true. I'm on my second one (replaced under warranty) and now this one is coming apart. I've attached photos of my original return and my replacement is doing the same thing. The strap just comes away from the body of the tracker. My replacement is not only doing it on the joins in the wrist strap, but also on the sides. It's just appalling that something this expensive should last less than a year.The buckle on the strap is not great. Yes it holds, but it's easy to catch on things and have it fall off or just come loose on it's own. I've nearly lost it on several occasions. The Charge HR sorts this problem, but still suffers from the awful build quality. I have friends with the Charge HR (bought because I loved my Charge to begin with) who have all had to get replacements due to failure within the first 12 months. One of them had 3 in a year because the charge port kept coming apart.The holes on the buckle tend to crack in the corners after a while. This means stepping up or down and is fine for a little while, but again means a very limited lifespan.I would NOT buy the Fitbit Charge again given my experiences. I still really like Fitbit and the app. The customer service has been excellent, but the Charge is just not fit for purpose. My previously mentioned friend who had 3 Charge HRs in a year eventually got a refund and bought the Blaze instead. That seems to be brilliant and because of the way it attaches to its bracelet it should fix all of the problems with the Charge and Charge HR. I'd get one of them if I were you or lot at the alternatives from other manufacturers.