Amazon.com is once again rumored to launch a smartphone in the second half of the year, the Wall Street Journal reported on Friday. The Internet retailer has recently been demonstrating versions of the handset to developers in San Francisco and Seattle. It intends to announce the device in June and ship to stores around the end of September, the newspaper cited the unidentified sources as saying.

Amazon will equip its phones with screens that display three-dimensional images without a need for special glasses, the Journal said.

Rumors of an Amazon-designed smartphone have circulated for years.

Apple and Samsung once accounted for the lion's share of the smartphone market but know they are struggling to maintain margins as new entrants such as Huawei and Lenovo target the lower-income segment.