"High" and "Low" (and the less often heard "Broad") church in Anglican usage refer to the different tendancies within Anglicanism which resulted from the Elizabethan compromise: uniform liturgy, no uniformity of doctrine beyond a few points on which protestants, Latins and Orthodox would all readily agree (and this came undone since the 1970's).
"High church" Anglican tend to maintain an 'Anglo-catholic' position, and will argue (reasonably) that Anglicanism isn't a protestant church. They favor the maintenance of ritual, have some clear understanding of the reality of the Eucharist, often are familiar with the Greek Fathers, and in exceptional cases will agrue that the Ecumenical Councils are the only standard for the exposition of the Faith beyond the Scriptures. Some 'High churchmen' (the Caroline divines, the non-Jurors, who were actually in union talks briefly, Bishop Grafton of Fond du Lac, who was
close to St. Tikhon when he was Arcbishop of Alaska and All North America) are as close to Orthodox as you will find among post-schism
Western Christians. An Orthodox monk of whom I am very fond has argued that the only Western group worth the Orthodox bothering to have 'ecumenical dialogs' with is a splinter group of high church Anglicans (the name of which I forget) who have dropped the filioque and declare themselves to adhere to the faith of the Seven Councils.
"Low church" Anglicans are basically C of E or Episcopalian evangelical protestants, though they are usually not Zwinglians in their Eucharistic theology, and "Broad church" Anglicans are liberal protestants, and are the group that extended 'Anglican inclusiveness' to apostates even from the minimal Christianity of the Elizabethan compromise.
Any or all of the persuasions may be very fond of the 1928 BCP. Ironically just as the Anglican apostacy really heated up in the 1970's the Prayer Book revisers decided to provide as an option among the Eucharistic prayers (all defective thanks to the lack of an eclepsis), the Anaphora of St. Basil the Great. I have the impression that most of the high churchmen who liked the option are now using the anaphora in its proper setting on the Sundays of Great Lent, the morning of Great and Holy Saturday, the Feast of the Circumcision, . . .
(My bishop once scandalized the Anglicans by thanking the main Anglo-catholic seminary in the U.S., Nashotah House, for sending him so many good priests.)
So, the outwardly was important -- uniformity of liturgy, damn the doctrine! As long as everything looks good on the outside. But, alas, churches that don't teach the same doctrine are not the same churches. But who cares! As long as they all got together and worshiped the same queen!