OnePlus 3T
BEST MID-RANG

OnePlus carved out a niche for itself in the mid-range segment, and the OnePlus 3T is the most refined offering from the company yet. Externally, there isn't a whole lot to differentiate it from the OnePlus 3, but the OnePlus 3T packs a more powerful Snapdragon 821 SoC, a 128GB storage option, a larger 3400mAh battery, and a new Gunmetal color option. The phone also picked up a new front camera, which is now a 16MP offering with 1-micron pixels. OnePlus has also committed to rolling out Nougat to the phone before the end of the year.

Other specs include 6GB of RAM, a 16MP rear camera, Wi-Fi ac, NFC, Bluetooth 4.2, and USB-C. The standard variant of the OnePlus 3T offers dual-SIM connectivity, so you don't have to look around for a specific variant to use with two SIM card slots.

There isn't a single global SKU, however. The North American model has different LTE bands from the Asian variant. If you pick up the phone in North America, you get the following LTE bands: 1/2/4/5/7/8/12/17/30. The model sold in Europe and India has these LTE bands: 1/3/5/7/8/20/38/40. The primary SIM card slot works over 4G, but the secondary is limited to 3G, and data is active on only work SIM at a time. The phone uses dual-standby mode, which means that only one SIM card slot is active during calls.

The 64GB variant of the OnePlus 3T retails for $439 in the U.S., with the 128GB model on sale for $479. In the UK, it costs £399 for the 64GB version, and £439 for the 128GB model. 

Bottom line: The OnePlus 3T gets all the basics right, and does so for several hundred dollars less than other flagships.

One more thing: If you're going to load up movies and music when you travel, you should consider the 128GB storage option.

BEST ON A BUDGET
Moto G4 Plus

The Moto G4 Plus isn't the fastest phone around, but it does offer a lot of value. The phone features a plastic body, but it doesn't feel cheap. Similarly, the internal hardware isn't outstanding, but it will serve you just fine for everyday use. There's a 5.5-inch Full HD display, Snapdragon 617 SoC, 16MP camera, microSD slot, 5MP camera, and a 3000mAh battery. Motorola has done a decent job of rolling out platform versions on time, and while the G4 Plus is slated to pick up the Nougat update shortly.

There are several configuration options of the G4 Plus available based on the region. You can get the phone with 2GB RAM/16GB storage, 3GB RAM/32GB storage, or 4GB RAM/64GB storage. Dual-SIM options also vary based on the country, but in markets like India and the UK, the dual-SIM variant is available direct from Motorola.

Bottom line: The Moto G4 Plus is still the benchmark for the budget segment. For under $250, this is the best option if you want two SIM card slots.

One more thing: Generally, you're better off selecting a model with at least 3GB of RAM and 32GB storage.

BEST FOR INDIA
Lenovo Z2 Plus

The Lenovo Z2 Plus is one of those rare phones that ticks all the right boxes in the budget segment. Available for the equivalent of $300 (₹19,999), you get a 5-inch Full HD display, Snapdragon 820 SoC, 4GB of RAM, 64GB storage, 13MP camera, 8MP front shooter, Wi-Fi ac, and a 3500mAh battery.

The phone is limited to Asian markets, and as such has LTE bands limited to the region: 1 (2100MHz), 2 (1900MHz), 3 (1800MHz), 4 (1700MHz/2100MHz), 5 (850MHz), 7 (2600MHz), 8 (900MHz), 38 (2600MHz), 39 (1900MHz), 40 (2300MHz), 41 (2500MHz). The phone offers a dual-standby mode, and as such only one SIM is active when you're on a call. The phone runs Android 6.0.1 Marshmallow, and Lenovo hasn't detailed Nougat update plans just yet.

Bottom line: The Lenovo Z2 Plus is an incredible value proposition. If you're on a tight budget, there isn't a phone that offers as much for under ₹20,000.

One more thing: As the Z2 Plus doesn't come with expandable storage, you should consider springing for the 64GB variant.

BEST OVERALL
Samsung Galaxy S7 edge

The Galaxy S7 edge is one of the most feature-rich phones available today. You get a gorgeous 5.5-inch dual curved Super AMOLED display, Samsung's own Exynos 8890 SoC, microSD slot, a 12MP camera that can hold its own, 5MP front camera, and a 3600mAh battery with wireless charging. There's also IP68 water resistance, which makes the phone immune to the occasional splash of water or a trip to the pool.

The carrier variants of the Galaxy S7 edge offer a single SIM card slot, but you can pick up an unlocked international model with dual-SIM connectivity (SM-G935FD). The unlocked models are costlier than carrier editions, but on the bright side, you don't have to deal with any bloatware.

Bottom line: If you're looking for a high-end phone with two SIM card slots, look no further than the Galaxy S7 edge.

One more thing: Your best bet for an unlocked Galaxy S7 edge with dual-SIM connectivity is the SM-G935FD. The phone is compatible with LTE bands in the U.S., UK, India, and Canada.