Latest Facebook Messenger 100 user agents:

User Agent Platform Device
Mozilla/5.0 (Linux; U; Android 4.3; es-us; SM-G7105L Build/JLS36C) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/MESSENGER;FBAV/100.0.0.29.61;] Android 4 Galaxy Grand 2
Mozilla/5.0 (Linux; U; Android 4.1.2; pt-pt; GT-I8730 Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/MESSENGER;FBAV/100.0.0.29.61;] Android 4 Galaxy Express
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/MESSENGER;FBAV/100.0.0.29.61;] Android 4 D500
Mozilla/5.0 (Linux; U; Android 4.1.2; en-au; GT-I8730T Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30 [FB_IAB/MESSENGER;FBAV/100.0.0.29.61;] Android 4 Galaxy Express
Mozilla/5.0 (Linux; Android 6.0; HUAWEI VNS-L31 Build/HUAWEIVNS-L31; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/62.0.3202.84 Mobile Safari/537.36 [FB_IAB/MESSENGER;FBAV/100.0.0.26.61;] Android 6 P9 Lite
Mozilla/5.0 (Linux; Android 6.0.1; Vodafone Smart ultra 6 Build/MMB29M; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/63.0.3239.111 Mobile Safari/537.36 [FB_IAB/MESSENGER;FBAV/100.0.0.29.61;] Android 6 Smart Ultra 6
Mozilla/5.0 (Linux; Android 6.0.1; SM-G903F Build/MMB29K; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/55.0.2883.91 Mobile Safari/537.36 [FB_IAB/MESSENGER;FBAV/100.0.0.29.61;] Android 6 Galaxy S5 Neo
Mozilla/5.0 (Linux; Android 6.0.1; SM-G900W8 Build/MMB29M; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/54.0.2840.85 Mobile Safari/537.36 [FB_IAB/MESSENGER;FBAV/100.0.0.29.61;] Android 6 Galaxy S5
Mozilla/5.0 (Linux; Android 6.0.1; SM-G900F Build/MMB29M; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/46.0.2490.76 Mobile Safari/537.36 [FB_IAB/MESSENGER;FBAV/100.0.0.29.61;] Android 6 Galaxy S5
Mozilla/5.0 (Linux; Android 6.0.1; HTC 2PST2 Build/MMB29M; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/50.0.2661.86 Mobile Safari/537.36 [FB_IAB/MESSENGER;FBAV/100.0.0.29.61;] Android 6 2PST2
Mozilla/5.0 (Linux; Android 5.0.2; LG-D722 Build/LRX22G.A1440040099; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/55.0.2883.91 Mobile Safari/537.36 [FB_IAB/MESSENGER;FBAV/100.0.0.29.61;] Android 5 G3S
Mozilla/5.0 (Linux; Android 4.4.2; VF695 Build/KOT49H) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/30.0.0.0 Mobile Safari/537.36 [FB_IAB/MESSENGER;FBAV/100.0.0.29.61;] Android 4 Smart First 6
Mozilla/5.0 (Linux; Android 4.4.2; CHC-U03 Build/HuaweiCHC-U03) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/30.0.0.0 Mobile Safari/537.36 [FB_IAB/MESSENGER;FBAV/100.0.0.29.61;] Android 4 G Play Mini
Mozilla/5.0 (iPad; CPU OS 10_2 seperti Mac OS X) AppleWebKit/602.3.12 (KHTML, seperti Gecko) Mobile/14C92 [FBAN/MessengerForiOS;FBAV/100.1.0.36.68;FBBV/46154306;FBRV/0;FBDV/iPad4,1;FBMD/iPad;FBSN/iOS;FBSV/10.2;FBSS/2;FBCR/;FBID/tablet; FBLC/en_US;FBOP/5] iOS 10 iPad Air
Mozilla/5.0 (iPad; CPU OS 10_2 like Mac OS X) AppleWebKit/602.3.12 (KHTML, like Gecko) Mobile/14C92 [FBAN/MessengerForiOS;FBAV/100.1.0.36.68;FBBV/46154306;FBRV/0;FBDV/iPad4,1;FBMD/iPad;FBSN/iOS;FBSV/10.2;FBSS/2;FBCR/;FBID/tablet;FBLC/ru_RU;FBOP/5] iOS 10 iPad Air
Mozilla/5.0 (iPad; CPU OS 10_2 like Mac OS X) AppleWebKit/602.3.12 (KHTML, like Gecko) Mobile/14C92 [FBAN/MessengerForiOS;FBAV/100.1.0.36.68;FBBV/46154306;FBRV/0;FBDV/iPad4,1;FBMD/iPad;FBSN/iOS;FBSV/10.2;FBSS/2;FBCR/;FBID/tablet;FBLC/en_US;FBOP/5] iOS 10 iPad Air