The original pair of AirPods aren't the smartest earbuds, but they're a good first step. They're easy to use, have good battery life and pair really well with a cellular Apple Watch.
Read this: The best hearables and smart buds to buy
So how - and when - could Apple top a success? There are a couple of ways.
In the short term, better Siri
While it may have fallen behind Google Assistant and Alexa, Siri is still a big deal for Apple. The company has worked to make it easier to use on the Apple Watch, for example, enabling the digital assistant with a simple wrist raise.
Siri isn't as easy to use on AirPods though, as you have to bring your hand up to your ear. Bloomberg reported that the second-generation AirPods would include a brand new wireless W2 chip that would enable better "Hey Siri" functionality. So instead of double tapping the AirPods to activate Siri, you could use say Apple's magic words. Plus, that W2 chip will improve its connection to your phone and likely improve battery life.
The other big feature is wireless charging, according to notorious tipster Ming-Chi Kuo. Apple already announced a version of AirPods that wirelessly charge, but those have disappeared (likely because the mystical AirPower charging mat has similarly disappeared). Apple is also likely to sell the wireless charging case separately so older AirPods users can get in on the fun.
These second-gen AirPods were rumored to debut at Apple's 30 October event, but that came and went and nothing happened. Kuo says the second-gen AirPods will see their release in the first quarter of 2019, which seems likely as we've seen them make their way through the Bluetooth Special Interest Group's regulatory database, as first spotted by MySmartPrice.
In the long term, biometrics
If you want a smarter pair of AirPods, you're going to have to wait until 2020 at least, according to Ming-Chi Kuo.
The third-generation AirPods are likely to be water resistant so that they could survive splashes of water, rain and sweat. You won't be able to swim with them or anything like that, but it's good to know you won't have to worry about them in bad weather.
The 2020 AirPods could also sport noise cancelling features, but a premium feature like that would also likely see the AirPods rise in price. Or, at the very least, come in multiple pricing tiers like the iPhone, according to Bloomberg.
Kuo also says that we're likely to see a redesigned version of AirPods in 2020. We don't exactly know what that means yet, but if Apple is planning on adding a number of new health features, a new design to pack in all that tech is likely. That sounds awfully like a newer patent from Apple shows a pair of earbuds with built-in health sensors and a more universal design.
A more advanced pair of AirPods with heart rate and ECG sensors is something that's definitely on Apple's mind, as evidenced by prior patent filings. Apple even updated its AirPods trademark to include a Class 10 designation in Hong Kong and Europe.
Class 10 is for devices intended for general wellness, and specifically describes "health, fitness, exercise, and wellness sensors, monitors, speakers and displays for measuring, displaying, tracking, reporting, monitoring, storing, and transmitting biometric data, heart rate, body movement, and calories burned".
Apple isn't huge on trends, and it usually doesn't push out products until sensors and components are affordable at scale and the time is ripe. Then it'll pounce. In the meantime, we'll have to wait and see when the more iterative versions of AirPods will arrive. Seeing as wearables are a big source of growth for Apple right now, it's a matter of when and not if.