This is almost the cheapest yet: $199.99 gets you the Sony Xperia M4 Aqua, which is still very much a powerful and desirable phone, from Amazon. This a new device, with the stock 16GB of storage and either the Black, White, Coral, or Silver color option, plus a standard warranty. It's a full $100 off of the retail price at which the Sony Xperia M4 Aqua launched a little over a year ago.
No contracts. No locked-in commitment to a specific carrier. The Sony Xperia M4 Aqua SIM unlocked smartphone gives you wireless freedom. With SIM unlocked, you have more choice when selecting a GSM service provider. The Sony Xperia M4 Aqua lets you capture memories anywhere with two excellent cameras, including a 13MP camera featuring Superior Auto technology, which recognizes 52 different scenes (including twilight and gourmet mode) and adjusts automatically for amazing photos. Xperia M4 Aqua’s waterproof design lets you use it where others cannot go – like when recording a video or taking photos at a concert in the rain. It also allows you to take your active lifestyle further thanks to a powerful battery that keeps your smartphone going for up to two days on a single charge.
Xperia M4 Aqua is compatible with GSM Networks, including AT&T, T-Mobile, and cellular network providers utilizing GSM network (such as Brightspot, Cricket Wireless, h20 Wireless, MetroPCS, Net10, Simple Mobile, Straight Talk and Walmart Family Mobile). Xperia M4 Aqua is not compatible with CDMA Networks such as Sprint, US Cellular and Verizon. It supports the following bands: GSM/EDGE (850, 900, 1800, 1900 MHz), UMTS/HSPA+ (850, 900, 1700/2100, 1900, 2100 MHz), and LTE (Bands 2, 4, 5, 7, 12, 13, 17).