Sarah Tew/CNET

I've reviewed tons of smartwatches. Or so it seems. And yet, I don't see many people wearing them. That's because the whole wearable landscape is embryonic. And, a lot of it's not very good.

By very good, I mean good of the type I'd recommend to my mom or my friend who's not into tech. Good as in, you need one of these. Or you'd want one. I can count on one hand the number of wearables that have gotten to that stage, and I wouldn't use all five fingers.

Smartwatches have come in many shapes and sizes: some have black and white screens. Some are big, bright and curved. Some run their own apps. Some have no apps at all. Some work with just Android. Others, iOS and Android. Some track fitness. Some do it better than others.

I had a list of what I was looking for in a killer wearable, Apple or otherwise, well over a year ago. A lot of my opinions there still stand. But now, as Apple might finally be ready to show off something big next week, how can it -- watch, band, or otherwise -- improve on what's out there?

Here's a good start.

Sarah Tew

Make it do three things better than any other gadget you already own

Smartwatches and wearables aren't necessary. They're additional gadgets in a world already flooded with gadgets. We don't need them. People need phones. People need computers. Tablets found a way to succeed to by doing some things so well that there was a desire to get one. It's the iPad equation: at first people called Apple's iPad a large iPhone. But it started up fast, had long battery life, and was a lot more portable than a laptop, and had a big screen.

What would a wearable do better than a phone or tablet or laptop? Track health? Pay for things? Stay connected with friends? It has to have its own purpose. Amazingly, beyond "act as a pager" or "count steps," most smartwatches right now don't.

Sarah Tew/CNET

A design that serves its function

Good-looking watches are one thing; a design that helps the wearable be good at what it does is far more important. Most watches go for flair: a curved screen, or a round face and super-thin bezel, or some premium material design. Do any of these make the wearable better at what it does? Sure, wristwatches are about design more than function. But when it comes to a killer smartwatch, I don't think it should work that way. MacBooks and iPads and iPhones are really well designed, but they're practically designed: they function. I don't want a fancy look if it doesn't make sense.

Work with things beyond your phone

Smartwatches are slaves to smartphones. They're glorified Bluetooth accessories. They can offer an on-wrist way to interact with stuff without checking your phone all the time, like on Google's Android Wear watches such as the Moto 360, but what about when you walk into a store, or an airport, or around your home?

Phones manage the relationship between smartwatches and other smart things and locations right now, but these wearables need to get smarter about where they are and what they're doing all on their own. Maybe, someday soon, we'll be in a world of connected things. Smartwatches should be ready to work with them and save us the extra drain on our phone.

Josh Miller/CNET

Battery life, battery life, battery life

Android Wear watches last about a day on a charge. The Pebble Steel and Meta M1 , 4 to 7 days. Most fitness bands, about a week. A few go for months, but have standard watch batteries.

It's a lot to ask for a small device to have killer battery life, but having yet another little thing to charge up is a gift no one I know cherishes. At the least, Apple's smartwatch or wearable will hopefully have a better, smarter way to conserve battery life, or recharge on the fly, or fast and effortlessly enough that it will remain functional. But some reports say that might not be the case. Maybe battery life on these types of devices just isn't ready to take the next step.

Wearables are meant to be worn all the time. The more they need recharging, the less they're worn, and the sooner they end up in a pile of discarded electronics.

Flexibility beyond a watch

Why does a wearable have to be a watch? Why can't it be more? The 2011 iPod Nano unclipped from a watchband and could be snapped on a jacket. It could be an accessory or a watch. Having something that could be swapped into different accessories with different styles, perform different functions in different situations, and be more of a universal multi-use mini-gadget...I'd far prefer that to any true watch.

Hundreds of accessory makers, fashion companies, and others could turn a flexible little device into a gadget with dozens of designs and forms. And it would make a lot more sense than creating a smartwatch with different physical shapes. The Misfit Shine is an activity tracker that takes this approach and succeeds as a watch, necklace, or clip-on.

Sarah Tew/CNET

Polished software

Google's Android Wear will transform rapidly over time: new features and improvements, and compatible apps are certain to make it better six months from now than it is now. But right now, it feels like a beta test. It doesn't do everything I want. Parts don't work reliably. It's fragmented.

If an Apple wearable debuts now, better to start small and do a few things really, really well. If those few things are great, and well-delivered, others can be introduced later. The iPhone didn't start with an App Store. But it had polished software for what it did right out of the gate.

Improve on the fitness equation

Most fitness wearables right now are, honestly, more of a carrot on a stick than a true way to improve daily fitness. Step-counting bands have limits as motivational tools. Heart-rate monitors on many recent smartwatches like Samsung's are buggy. Connected health-tracking hubs, like Withings, offer some good tools but don't always play well with everything else out there.

If Apple can make a hub using Health and Healthkit that allows for shared and exchanged health-tracking data between other accessories and apps, which senses your health and fitness more continuously, with better software coaching, there could finally be something worth getting beyond basic fitness bands.

I have other hopes, too, like a way to make secure payments from my wrist, but just nailing these would help Apple, and the whole wearable-tech industry, take a much-needed leap forward. Otherwise, for now, the outlook still currently feels stuck in beta.

Tune in to our live blog of Apple's September 9 event to find out more; we'll be there.