The Good: The Garmin Forerunner 235 has accurate GPS for tracking runs and a 24\/7 wrist-based heart-rate monitor. It can track all-day activities like steps and sleep, and can display notifications from iPhone and Android devices. It's water-resistant and can be worn in the shower or while swimming. The Bad: Heart rate accuracy drops off during interval training, there are occasional connection and syncing problems and Garmin's Connect app can be confusing to navigate. The Bottom Line: The Garmin Forerunner 235 offers the best value for serious and casual runners looking for an all-in-one running watch and fitness tracker. The was one of my favorite running watches of 2015. It was a device I personally recommend to numerous friends and family members, but there's a new king of the hill -- the Forerunner 235. The Forerunner 235 does everything both casual and serious runners would want. It has GPS to measure pace and distance when running, it has an optical heart-rate sensor, and it can track daily activities like steps and calories. These are all features shared with the Forerunner 225, but the 235 can do even more.It can display notifications from your iPhone or Android device and has access to Connect IQ, Garmin's third-party app store. It's also sleeker, more comfortable to wear, and like most of Garmin's products, it can be worn in the shower and while swimming. But one of the most appealing things about the Forerunner 235 is the price tag. The watch is available for $330, AU$469 or \u00a3270, only $30 more than what the Forerunner 225 was offered for. All in all, you now get way more value with little to no sacrifices.It's easily one of my new favorite watches for both casual and serious runners, but there's a few things you need to know before you go out and buy one. Changes from the Forerunner 225The Forerunner 235 adds more than a dozen new features to the 225. It's also thinner, lighter, has a higher resolution display and less of a bezel. The watch adds all-day heart rate tracking, smartphone notifications, music controls and access to Garmin's Connect IQ app store.On the fitness side of things, it includes support for GLONASS (the Russian GPS satellite alternative), which helps improve locating you in areas where GPS may be limited. There's also a feature for predicting your race times and a recovery advisor to help you determine when you're ready for that next hard workout. The watch can even estimate your VO2 Max (a metric used by athletes for measuring the maximum amount of oxygen that can be used during workouts). All of this is in addition to the basic running features like auto pause, auto lap, interval workouts and keeping track of your personal records.Running with the Forerunner 235 is enjoyable. It's comfortable to wear, the satellite signal is acquired almost instantly (even in New York), and it's pretty accurate. The recovery advisor seemed a bit off, as did my VO2 Max estimates, but they are just that -- estimates.As for you cyclists out there, while the watch is primarily for running, you do have the ability to pair ANT+ speed and cadence sensors. Unfortunately, there is no support for any Bluetooth sensors.The heart-rate sensor isn't perfectGarmin decided to use its own in-house technology, called Elevate, for the heart-rate sensor on the Forerunner 235. The method is similar to other sensors: Three green LED lights are used to light up the capillaries while the sensor measures how fast your blood flows past. Unlike with the Forerunner 225, the sensor on the 235 will run continuously throughout the day. Like its predecessor, I found the heart rate data to be relatively accurate. Resting heart rate fluctuated between 47 and 50 beats per minute (bpm), which is normal for me. Easy runs produced results similar to those recorded on a Polar H7 chest strap, although the 235 was delayed by between 3 and 6 seconds, but that's fairly common for optical sensors.