Microsoft's Lumia 640, 604 XL, 940, and 940XL release dates remain elusive despite being rumored for quite awhile. Even so, there are tidbits of information that might give a clue in regards to the launch schedule. We will explore these hints in the sections below.

Lumia 640, Lumia 640 XL

For now, only users in the U.K. can pre-order the Lumia 640 and Lumia 640 XL. This was confirmed in the latest report by Digital Trends, which also stated that U.S. customers will need to wait.

So far, three U.S. service providers have announced plans to sell the Lumia 640 and Lumia 640 XL. T-Mobile and MetroPCS will carry Lumia 640, while AT&T will sell the Lumia 640 XL. At this time, none of the companies have given release date information. However, desperate customers can buy the Microsoft Lumia 640 at Cricket Wireless for $129.99 with plan.

The Lumia 640 comes with a modest 5-inch display with 720p resolution. It is also powered by a Snapdragon 400 processor with 1 GB of RAM. Its rear camera is only capable of 8-megapixel, and has no flash. There is 8 GB of internal storage, and the option to store up to 128 GB via microSD card.

Larger than the Lumia 640, the Lumia 640 XL sports a 5.7-inch screen. The Lumia 640 XL is also expected to surpass the price of its smaller cousin. Both phones are destined to compete with a variety of top devices including the Samsung Galaxy S6, Motorola Moto X, Apple iPhone 6, and HTC One M9.

Lumia 940, Lumia 940 XL

Unfortunately, Microsoft has not confirmed the existence of either the Lumia 940 or Lumia 940 XL. There are rumors that both devices will be the first Microsoft handsets to be factory-installed with Windows 10. There have been additional whispers regarding the Lumia 940 and 940 XL specs. Naturally, all rumors need to be taken with a grain of salt.

Days ago, WMPowerUser revealed the alleged specs for the devices in question. The publication reported that Lumia 940 may have a 5.2-inch display, while the Lumia 940 XL may sport a 5.7-inch display. Both devices might share the same 20 MP rear camera, 3GB of RAM, and 32GB of internal storage. The Lumia 940 might have 3000mAH battery, while the Lumia 940 XL may come with a 3300mAH battery. Regarding processing power, the Lumia 940 XL may contain a Snapdragon 808 chipset.