Android's been around quite a while at this point (Google's Android turned 12 last year), and even Android phones have been around well over a decade now. And while obviously hardware like the HTC Hero matters in terms of where the platform got its start, and ones like the original Moto DROID mark its real entry into the marketplace in a big way, we think there are phones (and even A tablet) that are less remembered or less appreciated for their impact on the larger ecosystem.

After, when's the last time you thought of the Galaxy S2, or the HTC One M7? These were phones that weren't just good, they were phones that marked game-changing moments, each in their own important ways. You'll find them, along with eight others, profiled below.

Samsung Galaxy S2 - 2011

The Moto Droid established Android as a competitor to the iPhone, but the Samsung Galaxy S2 is why Android became mainstream. The combination of great hardware, good software, and Samsung's global presence propelled the Galaxy brand into widespread popularity - bringing Android along for the ride.

The Galaxy S2 was powered by an Exynos 4210 processor, with 1GB of RAM and 16GB of internal storage. It shipped with Android 2.3 Gingerbread, and was later updated to 4.1 Jelly Bean. The phone also included a few features uncommon at the time, like HDMI video out.

The Galaxy S2 received positive reviews for its performance, camera quality, and hardware build. It sold very well worldwide - 10 million units were shipped in the first five months. While the original Galaxy S was successful in its own right, the S2 cemented Samsung's position as the dominant maker of Android phones.

HTC ThunderBolt - 2011

Just because a product is a technological innovation doesn't mean it's good. In the Android world, there is perhaps no better evidence of that than the HTC ThunderBolt, originally released in 2011. The ThunderBolt was Verizon's first LTE-capable phone (the Samsung SCH-r900 was technically the world's first LTE device), but it gained a reputation for having absolutely terrible battery life.

The ThunderBolt came equipped with 786MB of RAM, 8GB of internal storage (with a 32GB microSD card pre-installed), a 4.3-inch 800x430 SLCD screen, and a 1,400mAh battery. Our review from 2011 pointed out the phone had a lot of bloatware, and most other reviews lamented about the battery life. CNET wrote, "with heavier 4G usage, we were scrambling for an outlet after 3 to 4 hours," and Engadget recommended "carrying a portable battery-powered micro-USB charger or a spare internal battery for peace of mind."

The ThunderBolt remains an important Android device for taking that first leap into the LTE future (in the US, anyway), but beyond that, it was a mediocre phone at best.

Motorola Xoom - 2011

The Motorola Xoom was Google's first (and arguably last) attempt at seriously competing with the iPad. It was the first device to ship with Android 3.0 Honeycomb, and it even had a commercial during the 2011 Super Bowl that parodied Apple's 1984 Super Bowl ad for the Macintosh.

The Xoom did have some features the iPad lacked, like a more desktop-like web browser (Chrome for Android wasn't available yet) and a full-size HDMI port. However, the $800 price tag was steep compared to the $499 iPad base model, there was no Adobe Flash support at launch, and if you thought there weren't many tablet-optimized Android apps now, the situation was even more grim in 2011. Granted, at least all the Google apps had tablet interfaces, which is something you can't say in 2019.

Unfortunately, the Motorola Xoom's success was short-lived. Sales dropped dramatically after a few months, and the Xoom 2 performed even more poorly.

The Xoom is one of the most important Android devices ever, not because it was successful, but because it was Google's only attempt at fighting the rising dominance of the iPad. While the later Nexus 7 did find some success, it was marketed primarily as a low-end media-consumption device, akin to the Amazon Fire tablets of today.

Future versions of Android slowly pulled back on the tablet-specific features, and 4.2 Jelly Bean drove the final nail into the coffin with its removal of the tablet navigation bar.

Kindle Fire - 2011

Speaking of tablets, the Kindle Fire is also an important milestone in the past decade of Android devices. Amazon's first tablet was released in 2011, and at the rock-bottom price of $199 (in a time when iPads were still $500), it sold like hotcakes.

The original Kindle Fire, much like the Fire tablets of today, wasn't a very powerful device. It had a TI OMAP dual-core CPU, 512MB of RAM, a 1024x600 LCD screen, 8GB of storage, and no SD card slot. However, the estimated eight hours of battery life and lightweight design made it a decent alternative to the iPad for reading books and streaming videos.

Again like modern-day Fire tablets, the Kindle Fire shipped with a heavily-modified version of Android (2.3 Gingerbread, in this case) with no Android Market. The Amazon Appstore was still in its infancy, but just like today, there was a large enough collection of applications and games for most people.

Amazon never provided solid sales numbers for the original Kindle Fire, only saying in 2011 that it was the "#1 bestselling, most gifted, and most wished for product" on Amazon.com. Estimates say around 7 million units were sold by 2013.

The Kindle Fire is an incredibly important device for a few reasons. It started a line of Fire tablets that remains incredibly successfully to this day, it helped cement Android as the go-to operating system for budget tablets, and the Amazon Appstore it popularized remains the only major competitor to the Google Play Store worldwide.

Samsung Galaxy Nexus - 2011

Android 4.0 Ice Cream Sandwich was a monumental update, and in my opinion, the first version that seriously competed with iOS. The new design language, Holo, made the operating system look and feel significantly better than Gingerbread. There were plenty of other functional enhancements too, like NFC support, face unlock, visual voicemail, and more. Since ICS was such an important release, it only makes sense that the first phone to run it — the Samsung Galaxy Nexus — would also be noteworthy.

The Galaxy Nexus was Samsung's second time manufacturing a phone for Google. It had a TI OMAP 4460 processor, 1GB of RAM, 32GB of storage (with no SD card slot), and a 4.65-inch 720p AMOLED screen. A 5MP camera was located on the back, and a 1.3MP shooter was on the front.

The phone received mostly positive reviews at launch. In our post from 2011, Ron wrote, "The hardware is great, the screen is beautiful, and it's the only phone that won't be saddled with OEM skins and waiting for updates. [...] This is, hands down, the best Android phone available. Go buy it." Seven years later, Ryne tried using the phone for a week, and it didn't go well.

Unfortunately, the glowing praise didn't last forever. The Galaxy Nexus suffered from low-quality flash storage and a lack of TRIM, which made the phone become sluggish for most users after a few months. Nexus phones becoming unusable after an extended period of time became a trend with future models.

Samsung Galaxy Note - 2011/2012

For several years, smartphone screens rarely passed 4 inches diagonally. This allowed them to be easily portable, but as applications become more feature-packed, the desire for larger displays became apparent.

Samsung answered the call for larger screens with the original Galaxy Note. It was released in Europe and other markets in late 2011, and it came to the United States in February of 2012. The phone had a 5.3-inch 800x1280 AMOLED screen, which was massive for the time, but small by today's standards.

Other specifications included a 1.5GHz Qualcomm Snapdragon CPU (or an Exynos processor outside the US), 1GB of RAM, 16GB of internal storage, and Android 2.3.6 Gingerbread. It also included the ever-useful S-Pen, which could be used to scribble notes and annotate screenshots.

As our review from 2012 points out, the Note was a great device when it was released. The screen was excellent (once you got used to the size), the battery life was great, and it supported 4G LTE. The only real downside was the software; it shipped with Gingerbread after Ice Cream Sandwich was released, and many of the apps didn't take advantage of the larger screen.

In less than two months, and before it even arrived in the US, the Galaxy Note passed one million units sold — proving that there was a market for larger devices. Other manufacturers eventually made competing phones, and Apple finally jumped on the big-screen bandwagon in 2014 with the iPhone 6.

HTC One M7 - 2013

HTC manufactured the first Android phone, and it has continued making devices with the OS to this day — in a limited capacity, anyway. Out of all the company's Android-powered devices, perhaps none was more influential in the smartphone industry than the One M7.

In a world dominated by plastic and glass smartphones, the One M7 stood out with its gorgeous aluminum design. The phone was also praised for its sharp 4.7-inch 1080p screen. In our review from 2013, David said, "You won't find a phone out there with a display that will make you happier than the One's for sheer beauty."

The One M7 also had dual front-facing speakers with Beats branding, a great rear camera, an IR blaster, and a revamped version of HTC's Sense skin. It was an all-around great device, and probably the peak achievement of HTC's smartphone division. Most importantly, the phone encouraged other manufacturers to produce all-aluminum devices.

Motorola Moto G - 2013

For what seemed like forever, all budget Android phones were horrible, poorly-built devices with outdated software. While there are still plenty of inexpensive phones in 2019 that match that description, the original Moto G earned a reputation for being the first not-terrible budget handset.

Motorola released the first Moto G phone in late 2013, at the low price of $179 (or $199 for the 16GB version). It was still mostly plastic, but the Snapdragon 400 processor paired with mostly-stock Android was enough for a solid experience. I should know, because I bought one after my Nexus 5 died.

A few months after the phone's release, a Google Play Edition came out with the same $179/$199 price tag. In mid-2014, a tweaked version with 4G LTE support came out, alongside the first Moto E phone. An actual second-generation model was released in September of that year, and the product line continues to this day.

OnePlus One - 2014

No list of important Android phones would be complete without the OnePlus One. In an era where the only 'budget flagship' you could buy was a Nexus 5, the OnePlus One made headlines with its $299 price tag. It had a modest plastic polycarbonate design with a 5.5-inch 1080p screen, but the Snapdragon 801 processor with 3GB of RAM made it a must-have.

The phone was also the first device to ship with CyanogenMod out of the box. Even though it was a great selling point at the time, the relationship between Cyanogen and OnePlus was rocky, and the two companies eventually stopped working together a year after the phone was released. In response, OnePlus developed its own OxygenOS ROM, which continues to be the stock software on OnePlus phones.

The OnePlus One didn't impact the smartphone industry on a grand scale, but it did solidify OnePlus as a favorite company among Android enthusiasts. After Google discontinued the Nexus lineup in 2016, OnePlus became the sole 'budget flagship' option for most people. The company is still releasing great value smartphones to this day.

Samsung Galaxy Fold - 2019

The Galaxy Fold's place in history isn't set in stone yet, since the phone was only released a few months ago. Still, it deserves a place on this list for being the first mass-market foldable smartphone.

The original Galaxy Fold design (note the lack of a covering around the display)

Samsung revealed the Galaxy Fold in February 2019, and the main attraction was the large 7.3-inch OLED screen that appeared when opening the device. However, the launch was delayed after the first wave of review units started failing, and all pre-orders were canceled pending changes to the manufacturing process.

The redesigned Galaxy Fold

The phone finally got its limited release in September 2019, and while the Galaxy Fold is still more fragile than your average smartphone, at least it won't completely break after a few days of regular use. If you're curious about how it holds up, we did a hands-on back in October.

Despite its manufacturing issues and still-questionable build quality, it deserves a place on this list for not just being the first foldable Android phone, but the first foldable phone period. This is a form factor we'll absolutely see more often in the coming years — Motorola, TCL, Xiaomi, Oppo, and others are already working on similar devices.