New mobile phone entrant Ymobile Corp. unveiled monthly fixed-price service plans Thursday that include voice calling and Internet access to woo newcomers to smartphones with simpler and cheaper contracts.

The SoftBank subsidiary, launched in June in a merger with eAccess, which runs Emobile, and Willcom, a PHS carrier, also revealed its first handset lineup.

The three data plans are the S plan, which charges ?2,980 per month for 1 gigabyte worth of data usage, the M plan, which costs ?3,980 for 3 GB of data, and the premium L plan, which costs ?5,980 for 7 GB a month.

All three come with 300 free 10-minute voice calls and will be available in August.

Ymobile President Eric Gan said only half of Japan¡¯s cellphone subscribers use smartphones, which is significantly lower than in markets like Singapore and South Korea.

He blamed this difference on Japan¡¯s expensive and complicated monthly plans.

¡°Let¡¯s make it simple and easy to understand,¡± he said.

The three established carriers, NTT Docomo, KDDI¡¯s au and SoftBank, charge ?2,700 for unlimited voice calls and ?3,500 for 2 GB worth of data usage per month.

Ymobile will also launch a service together with partner Yahoo Japan called Packet Mileage. Ymobile users will receive Mileage points when they use Yahoo Japan¡¯s services, including its home page or apps, it said.

The points can be exchanged for more data use capacity.