Apple’s next-generation iPhone will launch on Sprint’s network next month alongside AT&T and Verizon Wireless. In an effort to distinguish themselves from the competition, the third largest US wireless provider will offer an unlimited data service plan with Apple’s handset, says Bloomberg.

Sprint offers an unlimited data and talk package for smartphone users priced at $99.99 per month. Launching the iPhone 5 with a similar package could tempt current AT&T and Verizon customers on tiered plans to jump ship.

Both AT&T and Verizon initially offered unlimited data plans with the iPhone but have since moved to tiered plans. AT&T discontinued the package for new customers in June 2010 with Verizon following suit in July 2011. Customers who signed up for the plan before the switch were grandfathered in.

Evidence continues to mount which implicates Sprint as the next carrier to offer the popular smartphone.

The Wall Street Journal ran a story last month claiming Sprint would pick up the iPhone in mid-October. Last week a leaked Best Buy document indicated that the chain is expecting to take preorders for the iPhone 5 starting in October with Sprint listed as a carrier. Around the same time we reported that Sprint was raising their early termination and upgrade fees, possibly in a move to make a quick buck in the event that the carrier does release the iPhone next month.

The Bloomberg report also says that Sprint has postponed the launch of an unnamed 4G smartphone to prepare for the iPhone. Yesterday Sprint announced that they were delaying the BlackBerry Curve 9350 to October, although this isn't a 4G phone.