The LG G4 was very much unlikely to be unveiled at the MWC a few weeks from now, and recent reports in Korean media leave no doubt about that. An LG insider is quoted saying that the successor to the QHD-packing G3 flagship has an April launch date on its road map.
The Mobile World Congress in Barcelona will be a battle for attention between hotly-anticipated top-end smartphones from Samsung and HTC, and LG aims to distance itself from all that clamor. An April release will let the dust settle after the high-profile launches and let the spotlight shine solely on the LG G4. It's also not a full year after the LG G3 was introduced in May 2014, so there's no ground for complaints either.
We should note that LG already has a top-notch device in the face of the G Flex2 to compete with the other flagships upon launch. True, it's a bit eccentric, but a Snapdragon 810 with 3GB of RAM are high-end specs nonetheless, and can buy the company a few months of extra development time for the G4.