Latest Facebook 81 user agents:

User Agent Platform Device
Mozilla/5.0 (Linux; U; Android 4.3; en-us; ZTE-Z777 Build/JLS36C) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 4 Z777
Mozilla/5.0 (Linux; U; Android 4.3; en-us; ZTE-Z667G Build/JLS36C) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 4 Z667G
Mozilla/5.0 (Linux; U; Android 4.1.2; es-us; ZTE-Z995 Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 4 Z995
Mozilla/5.0 (Linux; U; Android 4.1.2; es-us; ZTE-Z740 Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 4 Z740
Mozilla/5.0 (Linux; U; Android 4.1.2; es-us; G527-U081 Build/HuaweiG527-U081) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 4 Ascend G527
Mozilla/5.0 (Linux; U; Android 4.1.2; es-ar; LG-E410g Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 4 Optimus L1 II
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/81.0.0.22.70;] Android 4 Z998
Mozilla/5.0 (Linux; U; Android 4.1.2; en-us; ZTE-Z740G Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 4 Z740G
Mozilla/5.0 (Linux; U; Android 4.1.2; en-au; LG-E435k Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 4 Optimus L3 II
Mozilla/5.0 (Linux; U; Android 4.0.4; es-es; GT-S5301L Build/IMM76D) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 4 Galaxy POCKET Plus
Mozilla/5.0 (Linux; U; Android 4.0.4; en-us; LG-AS730 Build/IMM76L) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 4 AS730
Mozilla/5.0 (Linux; U; Android 4.0.3; en-ca; HTC-X710a Build/IML74K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 4 X710a
Mozilla/5.0 (Linux; Android 6.0.1; vivo 1603 Build/MMB29M; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/52.0.2743.98 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 6 Y55l
Mozilla/5.0 (Linux; Android 5.1; VF-696 Build/LMY47I; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/51.0.2704.81 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 5 Smart Grand 6
Mozilla/5.0 (Linux; Android 5.1; HTC Desire 626 Build/LMY47O; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/51.0.2704.81 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 5 Desire 626
Mozilla/5.0 (Linux; Android 5.1.1; vivo 1613 Build/LMY47V; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/95.0.4638.74 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 5 Y25
Mozilla/5.0 (Linux; Android 5.1.1; SM-A5100 Build/LMY47X; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/45.0.2454.95 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 5 Galaxy A5 (2016)
Mozilla/5.0 (Linux; Android 5.1.1; SAMSUNG-SM-G800A Build/LMY47X; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/51.0.2704.81 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 5 Galaxy S5 mini
Mozilla/5.0 (Linux; Android 5.1.1; HUAWEI SCC-U21 Build/HuaweiSCC-U21) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/39.0.0.0 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 5 Y6
Mozilla/5.0 (Linux; Android 5.0.2; MEO Smart A80 Build/LRX22G; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/51.0.2704.81 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/81.0.0.22.70;] Android 5 MEO Smart A80