Two of the largest online cell phone discounters are battling it out with Back To School sales online. Both are offering a selection of free phones with the purchase of plans. Both are also offering free activation on plans purchased on the Sprint Network.

The first sale we will look at is from a cell phone outlet called Wirefly. They are promoting their sale as the “Back To School Free Android Event”. Here’s a list of cell phones that come free with the purchase of a new, 2 year, plan from the indicated carrier. Motorola DROID 2 Global on Verizon; myTouch 4G Black on T-Mobile; DROID X on Verizon; HTC EVO 4G on Sprint (free activation); CASIO GzOne Commando on Verizon; Samsung Exhibit 4G Black on T-Mobile; Samsung Fascinate on Verizon; Samsung Transform on Sprint (free activation); LG Vortex Black on Verizon; and the HTC EVO Shift 4G on Sprint (free activation).

The free activation on Sprint lines comes as a $36 per-line credit, with a limit of 5 lines ($180). The free activation offer is only good until Monday, July 25.

The second sale is being offered over at LetsTalk. Their “Back To School” sale includes free, with the purchase of a new 2 year plan, the Xperia Play; DROID Incredible 2 by HTC; the HTC Trophy; DROID 2 Global by Motorola Dark Sapphire; Samsung Fascinate; Casio’s G’zOne Commando; Pantech Crux; Samsung Continuum; and a few others on the Verizon Network. The HTC EVO 3D; the Sanyo Taho; LG Optimus S Purple; Samsung Replenish; Palm Pixi; BlackBerry Curve 3G; BlackBerry Style 9670 Steel Grey; Samsung Transform; Sanyo Vero; the Motorola XPRT, and others on the Sprint Network (also with free activation). On the T-Mobile network, they have the Nokia Astound; Samsung Exhibit 4G; LG Optimus T Titanium; the T-Mobile Comet; BlackBerry Curve 3G 9300 Graphite Grey; Samsung Gravity T; Samsung Gravity Smart; the Samsung 🙂 and the LG GS170.

Interestingly enough, LetsTalk says their free Sprint activation special is good until Tuesday, the 26th. One day longer than Wirefly’s.