Latest Facebook Messenger 175 user agents:

User Agent Platform Device
Mozilla/5.0 (Linux; U; Android 4.2.2; pt-pt; GT-S7582 Build/JDQ39) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 4 Galaxy S DUOS 2
Mozilla/5.0 (Linux; U; Android 4.2.2; pt-pt; ALCATEL ONE TOUCH 7041X Build/JDQ39) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.2 Mobile Safari/534.30 SVN/070FPG1 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 4 One Touch Pop C7
Mozilla/5.0 (Linux; U; Android 4.1.2; pt-pt; LG-E460 Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 4 Optimus L5 II
Mozilla/5.0 (Linux; U; Android 4.1.2; pt-pt; GT-I9100 Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 4 Galaxy S II
Mozilla/5.0 (Linux; U; Android 4.1.2; pt-pt; GT-I8190 Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 4 Galaxy S III mini
Mozilla/5.0 (Linux; Android 8.1.0; VFD 720 Build/O11019; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/64.0.3282.137 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 Smart N9
Mozilla/5.0 (Linux; Android 8.1.0; TA-1033 Build/OPR1.170623.026; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/68.0.3440.70 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 6
Mozilla/5.0 (Linux; Android 8.1.0; TA-1024 Build/OPR1.170623.026; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/68.0.3440.85 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 5
Mozilla/5.0 (Linux; Android 8.1.0; TA-1004 Build/OPR1.170623.026; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/67.0.3396.87 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 8
Mozilla/5.0 (Linux; Android 8.1.0; Nokia 1 Build/O11019; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/65.0.3325.109 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 1
Mozilla/5.0 (Linux; Android 8.1.0; Nexus 5X Build/OPM2.171026.006.H1; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/67.0.3396.87 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 Nexus 5X
Mozilla/5.0 (Linux; Android 8.1.0; Mi A1 Build/OPM1.171019.026; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/68.0.3440.70 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 Mi A1
Mozilla/5.0 (Linux; Android 8.1.0; DRA-L21 Build/HUAWEIDRA-L21; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/67.0.3396.87 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 Y5 (2018)
Mozilla/5.0 (Linux; Android 8.0.0; WAS-LX1A Build/HUAWEIWAS-LX1A; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/68.0.3440.70 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 P10 Lite
Mozilla/5.0 (Linux; Android 8.0.0; WAS-LX1A Build/HUAWEIWAS-LX1A; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/67.0.3396.87 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 P10 Lite
Mozilla/5.0 (Linux; Android 8.0.0; VTR-L09 Build/HUAWEIVTR-L09; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/67.0.3396.87 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 P10
Mozilla/5.0 (Linux; Android 8.0.0; TA-1032 Build/O00623; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/67.0.3396.87 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 3
Mozilla/5.0 (Linux; Android 8.0.0; TA-1020 Build/O00623; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/67.0.3396.87 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 3
Mozilla/5.0 (Linux; Android 8.0.0; SM-G950F Build/R16NW; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/67.0.3396.87 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 Galaxy S8
Mozilla/5.0 (Linux; Android 8.0.0; SM-G935F Build/R16NW; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/67.0.3396.87 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/175.0.0.23.81;] Android 8 Galaxy S7 Edge