One of the controversial issues about the new Apple Watch is its battery life, where unlike other smart watch offerings that give you days of use, the battery is slated to last about a day before you need to charge it; however, this is only under a generalized usage condition. Under heavy usage, the battery is claimed to last 5 hours. While these claims are out by Apple, as with its MacBook batteries, those interested in the Apple Watch will likely view this with a skeptical eye and be truly interested in how long the watch will last, both under their desired uses, and over time. Here is a more in depth breakdown of what to expect from the Apple Watch’s battery.

First off, the watch should charge in about 2 hours, which means that you can get to about 80 percent charge by 1.5 hours, and up past 50% charge by about an hour. However, for a full charge, be prepared to let it stand a little longer, up to about 2.5 hours. Therefore, be you might consider setting up your various workstations with chargers for the watch, so you can keep it functional throughout your workday. Apple offers its magnet chargers at $29 and $39, depending on cord length.

The Extreme Uses

According to Apple, while it claims under normal uses the Apple Watch will get about 18 hours of battery life, and 5 hours under heavy usage, there are the extreme uses that will drastically change this. If you use the watch constantly for voice communication, and invoke Siri regularly, then this 5-hour range drops to about 3 hours. This amount increases slightly to just over 5 hours if you use the watch for constant media handling, such as listening to music.

On the other hand, without much use you ought to get more than Apple’s claimed 18-hour time frame if you use your watch minimally. By turning off most notifications and background services, and instead using the watch as a time piece only, you should be able to get about two days of use out of the thing; however, this will defeat the purpose of using the watch. At the highest extreme, you can use the Power Reserve mode on the Apple Watch (a special mode that cuts out all services except time keeping) at all times. In this mode, the watch should be able to run for several days.

Apple’s 18-hour Usage

The advertised ranges that Apple has been sticking to suggest activity for most people by Apple’s estimates, which are that you keep your watch out of Power Reserve mode (which is intended for battery preservation and will kick in automatically when the battery is low), and then use your watch in the following manner:

• Check your watch only a few times per hour.
• Use apps for no more than an hour in total.
• Receive under 100 notifications from the apps you have over the course of the day.
• include one 30-45 minute workout that uses the bluetooth antenna for music and fitness apps.

Overall, Reduce Bluetooth Usage

In all of these cases, the primary draw on your Apple Watch’s battery is the use of its Bluetooth and Wi-Fi antennas (which similarly contributes to power drain on some MacBook systems). Therefore, if you set it up to minimally activate these antennas, then you will get the longest battery life out of your watch.

Batteries Over Time

Finally, keep in mind that these estimates are based on a fresh and new battery in your watch. Apple has made some nice advancements to battery technology in recent years; however, for any rechargeable battery, over time and use, and in different environmental conditions, they will perform differently and inevitably hold less charge. Apple has not commented on the possibility of servicing the watch to replace a faulty or worn out battery, but if they behave anything like Apple’s current MacBooks, then expect after regular use for a couple years, that you will only be able to charge it to 80 percent of its initial capacity, or less.