Latest Facebook 40 user agents:

User Agent Platform Device
Mozilla/5.0 (Linux; U; Android 4.3; en-us; ZTE-Z669 Build/JLS36C) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 Z669
Mozilla/5.0 (Linux; U; Android 4.3; en-us; HUAWEI C8816D Build/HuaweiC8816D) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 C8816D
Mozilla/5.0 (Linux; U; Android 4.2.2; en-us; Micromax A47 Build/JDQ39) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 A47
Mozilla/5.0 (Linux; U; Android 4.2.2; en-in; Micromax A114 Build/JDQ39) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 A114
Mozilla/5.0 (Linux; U; Android 4.1.2; es-us; GT-S6810E Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 Galaxy FAME
Mozilla/5.0 (Linux; U; Android 4.1.2; es-ar; LG-E451g Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 E451g
Mozilla/5.0 (Linux; U; Android 4.1.2; en-us; ZTE-Z998 Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 Z998
Mozilla/5.0 (Linux; U; Android 4.1.2; en-us; SCH-I200PP Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 Galaxy Stellar
Mozilla/5.0 (Linux; U; Android 4.1.2; en-us; LG-P875h Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 Optimus F5
Mozilla/5.0 (Linux; U; Android 4.1.1; en-us; ZTE-Z993 Build/JRO03C) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 Z993
Mozilla/5.0 (Linux; U; Android 4.1.1; en-us; ZTE-Z992 Build/JRO03C) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 Avail 2
Mozilla/5.0 (Linux; U; Android 4.0.4; en-us; LG-LS860 Build/IMM76I) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 LS860
Mozilla/5.0 (Linux; U; Android 4.0.4; en-us; HUAWEI M868 Build/HuaweiM868) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 M868
Mozilla/5.0 (Linux; U; Android 4.0.3; en-us; HUAWEI U8681 Build/HuaweiU8681) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 U8681
Mozilla/5.0 (Linux; Android 4.4.2; SM-N900J Build/KOT49H) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/30.0.0.0 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 Galaxy Note 3
Mozilla/5.0 (Linux; Android 4.4.2; LG-D120 Build/KOT49I.A1404304792) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/30.0.0.0 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 L30
Mozilla/5.0 (Linux; Android 4.4.2; HTC_D610x Build/KOT49H) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/30.0.0.0 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/40.0.0.24.199;] Android 4 Desire 610
Mozilla/5.0 (iPod touch; CPU iPhone OS 9_3_5 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Mobile/13G36 [FBAN/FBIOS;FBAV/40.0.0.42.290;FBBV/15252421;FBDV/iPod5,1;FBMD/iPod touch;FBSN/iPhone OS;FBSV/9.3.5;FBSS/2; FBCR/;FBID/phone;FBLC/en_US; iOS 9 iPod Touch 5
Mozilla/5.0 (iPod touch; CPU iPhone OS 9_3_2 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Mobile/13F69 [FBAN/FBIOS;FBAV/40.0.0.42.290;FBBV/15252421;FBDV/iPod5,1;FBMD/iPod touch;FBSN/iPhone OS;FBSV/9.3.2;FBSS/2; FBCR/;FBID/phone;FBLC/en_US; iOS 9 iPod Touch 5
Mozilla/5.0 (iPad; CPU OS 9_3_5 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Mobile/13G36 [FBAN/FBIOS;FBAV/40.0.0.42.290;FBBV/15252421;FBDV/iPad3,1;FBMD/iPad;FBSN/iPhone OS;FBSV/9.3.5;FBSS/2; FBCR/;FBID/tablet;FBLC/en_GB;FBOP/1] iOS 9 iPad 3