By Sinead Carew NEW YORK (Reuters) – Sprint Corp on Tuesday unveiled a new option called framily plans that give up to 10 family members or friends big service discounts if they sign up as a group, the latest move in an increasingly competitive market. The new option, which could represent a service discount of almost 50 percent from Sprints existing family plan in some cases, follows aggressive discounts by Sprints smaller rival T-Mobile US that sparked a new wave of competition. T-Mobiles chief executive officer put the spotlight on family plans last week when he said winning over rivals family plan users was a New Years resolution. T-Mobile is seen as an acquisition target by Sprint, which is 80 percent-owned by SoftBank Corp. Operators have long offered discounts through family plans because they help to retain customers as it is harder for groups to switch than for individual customers.