Please check the compatible with ipad models. You can see model number (AXXXX) on the back of your iPad.
Compatble with iPad 2018 Releases and Later:
iPad Pro 12.9inch 3th 4th 5th Gen - A2229/A2069/A2232/A2233/A1876/A2014/A1895/A1983/A2378/A2379/A2461/A2462
iPad Pro 11inch 1th 2th 3th Gen - A2229/A2069/A2230/A2231/A1980/A2013/A1934/A1979/A2377/A2459/A2301/A2460
iPad 6th 7th 8th 9th Gen - A2430/A2602/A2604/A2603/A2605
iPad Air 3rd 4th 5th Gen - A2152/A2123/A2153/A2154/A2316/A2324/A2325/A2072/A2588/A2589/A2591
Ipad Mini 5th 6th Gen - A2133/A2124/A2126/A2125/A2567/A2568/A2569
Not compatible with the ipad release before 2018 and not work with iPhone, Android, Microsoft Devices.
iPad Pro 9.7inch - A1673/A1674/A1675
iPad Pro 10.5inch - A1701/A1709/A1852
iPad Air 1-2 Gen - A1474/A1475/A1476/A1566/A1567
iPad Pro 12.9inch 1-2 Gen - A1584/A1652/A1670/A1671/A1821
iPad Mini 1-4 Gen - A1432/A1454/A1455/A1489/A1490/A1491/A1599/A1560/A1538/A1550
iPad 1-5 Gen - A1219/A1337/A1395/A1396/A1397/A1416/A1430/A1403/A1458/A1459/A1460/A1822/A1823