LG G4 release date is set for June 4, and pre-order sales have started at various U.S carriers. These include T-Mobile, Sprint, AT&T and Verizon. In the meantime, LG G3 and G2 owners are still awaiting the Android 5.1 Lollipop. This update will fix a number of bugs reported in the previous Android 5.0 Lollipop update.

LG G4 Pre-Order Sales Begin at Four Major Wireless Service Providers

Last month, Sprint and T-Mobile were the first carriers to kick off LG G4 presales. Verizon came next, offering LG G4 preorders on May 28. The next day, AT&T followed suit. In total, there are now four nationwide U.S. carriers that are selling the LG G4.

T-Mobile's G4 comes in either Metallic Gray or Genuine Brown Leather. The basic device costs up to $600, but buyers have the option to pay a monthly $25 over 24 installments.

AT&T's G4 comes in Metallic Gray or Genuine Black Leather. The starting price for a basic G4 is $629.99. With Black Leather cover, the price jumps up to $669.99. Should subscribers purchase a 2-year plan, the Metallic Gray version costs only $199.99.

Verizon and Sprint's G4 have the same color options as AT&T. However, the full price of a basic Sprint G4 is $600. Verizon's LG G4 is the cheapest at $549.99. Naturally, both carriers offer lower prices for consumers who buy 2-year plans.

Android 5.1 Lollipop for LG G3 and G2 Still Missing

Earlier this year, the Android 5.0 Lolliop began rolling out to the LG G3 and G2 flagship devices. Generally, consumers reported positive experiences with the new update. A number of critics praised the Lollipop's improvements that included enhanced performance, increased battery life, and well-designed notification bar.

However, other users experienced overheating, freezing, app crashes, significant battery drain, and random reboots. The latest Android 5.1 Lollipop update is said to fix a number of issues associated with Android 5.0 Lollipop.

There is still no word from LG regarding whether the LG G3 and G2 will receive Android 5.1 Lollipop. In contrast, Android 5.1 Lollipop is already included with the new LG G4 flagship device.

Also, Google is starting to roll out the Android 5.1.1 Lollipop OTA to Nexus devices. It is not clear whether LG plans to skip Android 5.1 Lollipop in favor of the newest Android update.