Japanese cellco Softbank Mobile is reportedly planning to cut its smartphone charges by introducing a flat rate for unlimited voice calling and cheaper data plans from July, Reuters reports. In addition to flat-fee unlimited voice calling, Softbank Mobile is also expected to offer its users the possibility of transferring unused data from month to month, as well as the opportunity to share a data allowance with other family members; the operator also plans to launch a number of special offers and discounts for family plans, long-term users and subscribers aged 25 and under. The new flat-rate plans resemble the bundles recently introduced by rival NTT DOCOMO, hinting that price competition may be heating up in Japan's wireless market.*According to TeleGeography's CommsUpdate, in April 2014NTT DOCOMO revealed that it was planning to introduce a new billing plan, dubbed 'Kake-hodai & Pake-aeru', which would enable all subscribers to make nationwide voice calls for a flat monthly rate. Furthermore, the plan enables customers to set and share their monthly data allowance with family members or corporate users, depending on what type of mobile device they are using. In total, customers are able to choose from six types of basic monthly fees and seven levels of data-quota sharing (21 levels for corporate users); the move was designed as an attempt to encourage multi-device ownership and facilitate migration to smartphone adoption in order to boost data revenues. The billing plan is available for smartphones, mobile handsets and M2M devices.