Mobile World Congress is easily the biggest mobile phone show of the year. While its January cousin, CES, may be waning in mobile relevance, MWC still reliably brings us major new flagship smartphones every year. Last year saw the launch of the Samsung Galaxy S6 and HTC One M9, but what should we expect this year? What follows is a roundup of the more believable rumors that are floating around out there.

Samsung, LG, and Xiaomi all have events at the show and are all expected to launch their new flagships. The major additions to just about every 2016 Android flagship will be the new Snapdragon 820, and with the addition of Android 6.0 Marshmallow's fingerprint reader support, if a device didn't come with a fingerprint reader before, it will now.

Samsung Galaxy S7—The S6 design gets a spec bump and 3D Touch

Samsung typically headlines the MWC festivities, and this year a big "Galaxy Unpacked 2016" press event is scheduled for February 21. Samsung launched the all-new Galaxy S6 and Galaxy S6 Edge at Mobile World Congress 2015, and this year we can expect it to follow the same formula with the Galaxy S7 and S7 Edge.

The Galaxy S6 was all new last year, switching from a plastic body to a mostly glass device with a metal band around the side. Samsung also introduced an "Edge" variant, which featured a screen that curved along the left and right sides. It's rare to see a company do back-to-back redesigns, and this year it seems the Galaxy S7 will stick pretty close to the Galaxy S6 formula. A report from The Wall Street Journal has said the S7 "will look largely similar" to the S6, and press renders have been steadily leaking from Evleaks that mostly fit with this report.

There do seem to be a few minor tweaks based on the pictures. The regular Galaxy S7 has a flat front but seems to have picked up a curved back, just like the Galaxy Note 5. The top and bottom of the Galaxy S7 Edge seem to be rounded now to better match the curved screen. It also looks like both devices have a smaller camera hump—it's nearly flush with the back now.

With the move to a more solid body, the Galaxy S line lost its removable back, removable battery, and MicroSD card. This is more in line with the rest of the industry, but some customers were drawn to Galaxy phones specifically for these features. Samsung won't be doing anything about the battery, but multiple reports have said the MicroSD card is making a comeback.

The removal of the SD card on the Galaxy S6 was a victim of really bad timing. MicroSD card support got a lot better in Android 6.0 Marshmallow , just as Samsung removed it from its flagship devices. Marshmallow added the ability to turn removable storage into "permanent" internal storage , which treats the internal and SD card as a single pool of storage. This is pretty much the dream scenario for internal storage—letting a user pop in a card, format it, and forget about it—seamlessly boosting the internal storage.

As for new features, the same WSJ report notes that the Galaxy S7 will have a "pressure-sensitive display" which "will be similar to that offered by rival Apple Inc. on the iPhone 6s earlier this year." The screen sizes will apparently change a bit from what they've been in the past. A report from the Economic Times of Korea claims the S7 will be a 5.2-inch device—0.1 inches bigger than last year, but the big change is coming to the S7 Edge, which would grow to 5.5-inches. Both devices are apparently getting a 1440p display again—good news for battery life but bad news for anyone hoping for a better quality Galaxy Gear experience.

There might be a bit of disappointment brewing regarding the Galaxy S7's USB port. The Wall Street Journal has said that the S7 will ship with the increasingly standard-issue USB Type-C plug, but more recent leaks show a device that still has a MicroUSB plug. Maybe Samsung is aiming to keep compatibility with the Galaxy Gear, since a Type C plug would necessitate a whole new headset.

As for the internals, VentureBeat is reporting that Samsung will return to an SoC strategy that sees the US version ship with a Qualcomm chip while international releases get Samsung's own Exynos line. The report says the international version will get an Exynos 8 Octa 8890 SoC, while the US version will ship with a chip we'll probably be very familiar with soon, the Qualcomm Snapdragon 820. VentureBeat also claims the S7 will ship with a whopping 4GB of RAM.

We also might see the Galaxy S line return to a water-resistant build. The Galaxy S5 was water-resistant, complete with USB covers, but the feature was omitted from the Galaxy S6. A leaked promotional video for the Galaxy S7 shows it being used in the rain, which suggests Samsung will return to a water-resistant design.

We don't know the battery size for the smaller Galaxy S7, but the 5.5-inch Galaxy S7 Edge apparently has a 3600mAh battery, according to FCC documents spotted by SamMobile. The 5.7-inch Galaxy Note 5 only has a battery capacity of 3020mAh, so while the battery won't be removable, it seems like Samsung has focused on packing in a little more power than the previous generation.

The LG G5—Wild rumors of a metal phone with a modular "Magic Slot"

Speaking of removable batteries, the LG G5 will be debuting at Mobile World Congress. LG sent out the above invite to the press for its MWC event, along with a note to expect "LG's next flagship model" at the show. The timing is a big change for LG—the company doesn't usually go toe-to-toe with Samsung. If the rumors turn out to be true, though, LG could have the standout device of MWC.

After Samsung nixed removable batteries and storage from its lineup, the LG G4 stood alone last year as the only major flagship with replaceable components. The G5 will supposedly continue these features—no surprise there—but the real shocker is that rumors are also claiming it will switch to a metal body. No OEM in recent history has pulled off a metal phone with a removable battery—usually you get a plastic body with a removable back or a sealed metal phone.

LG will apparently manage to pull off a modular metal phone design with something called the "Magic Slot"—that's according to reports from VentureBeat, The Verge, and CNET Korea. CNET actually produced a render "based upon eyewitness testimony" that shows the bottom of the phone detaching and the battery sliding out the same way you would remove a deck of cards from a box. The reports also mention "modular accessories" that could go into the Magic Slot, with VentureBeat saying, "The examples we were given range from an array of specified cameras — action, 360 VR, “party” — to an audio amplifier to a physical keyboard."

Of course, internally, the LG G5 will use the Qualcomm Snapdragon 820—expect the 820 to ship in nearly every major flagship this year. Hopefully it won't have the heat issues that were present on the Snapdragon 810, and all of Qualcomm's early performance boasts will turn out to be true.

LG is apparently also going to take advantage of one of the stranger features present on both the Snapdragon 810 and 820—dual rear cameras. We last saw this feature on the HTC One M8, which would use the dual rear cameras to simulate the depth-of-field you would get from a real camera. We weren't fans of the inaccurate, artificial blur lines on the One M8, and HTC removed the feature when it was time to design the M9. Perhaps two years of improvement will result in something a little more accurate, though.

Several reports and case renders show LG skipping out on the unique rear volume buttons and moving them to the normal spot on the side of the phone. The back of the device will still reportedly be a busy place, with two cameras, LG's laser auto focus and color sensor from the G4, LED Flash, and a fingerprint reader like the LG Nexus 5X.