Latest Facebook 84 user agents:

User Agent Platform Device
Mozilla/5.0 (Linux; U; Android 4.3; es-us; ZTE-Z777 Build/JLS36C) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 4 Z777
Mozilla/5.0 (Linux; U; Android 4.3; es-us; HUAWEI Y530 Build/HuaweiY530-U051) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 4 Ascend Y530
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/84.0.0.20.70;] Android 4 Z777
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/84.0.0.20.70;] Android 4 Z669
Mozilla/5.0 (Linux; U; Android 4.2.2; pt-pt; ME173X Build/JDQ39) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Safari/534.30 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 4 MeMO Pad HD 7
Mozilla/5.0 (Linux; U; Android 4.1.2; es-mx; LG-E612g Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 4 Optimus L5
Mozilla/5.0 (Linux; U; Android 4.1.2; en-us; LG-D500 Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 4 D500
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/84.0.0.20.70;] Android 4 Avail 2
Mozilla/5.0 (Linux; U; Android 4.0.4; es-mx; LG-P925 Build/ICS) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 4 P925
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/84.0.0.20.70;] Android 4 LS860
Mozilla/5.0 (Linux; U; Android 4.0.3; es-mx; LG-P708g Build/IML74K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 4 P708g
Mozilla/5.0 (Linux; Android 6.0; EVA-L09 Build/HUAWEIEVA-L09; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/51.0.2704.81 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 6 P9
Mozilla/5.0 (Linux; Android 6.0.1; SM-N930R4 Build/MMB29M; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/49.0.2623.105 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 6 Galaxy Note 7
Mozilla/5.0 (Linux; Android 5.1; SELFIX_X6_GLAS Build/LMY47D) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/39.0.0.0 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 5 Unknown
Mozilla/5.0 (Linux; Android 5.1; SELFIX_Q5_URBAN Build/LMY47I) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/39.0.0.0 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 5 Q5 Urban
Mozilla/5.0 (Linux; Android 5.1.1; Y538 Build/HuaweiY538) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/39.0.0.0 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 5 Y538
Mozilla/5.0 (Linux; Android 5.0; SELFIX_SLASH6 Build/LRX21M) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/37.0.0.0 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 5 Slash 6
Mozilla/5.0 (Linux; Android 5.0.1; SCH-I959 Build/LRX22C; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/43.0.2357.121 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 5 Galaxy S4
Mozilla/5.0 (Linux; Android 4.4.4; SM-T116NU Build/KTU84P) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/33.0.0.0 Safari/537.36 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 4 Galaxy Tab 3 V
Mozilla/5.0 (Linux; Android 4.4.2; LG-D681 Build/KOT49I) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/30.0.0.0 Mobile Safari/537.36 [FB_IAB/FB4A;FBAV/84.0.0.20.70;] Android 4 G Pro Lite