Much of the post-announcement hoo-hah centered on the aforementioned companies, but a quick peek in Google Play reveals a slew of alternatives. For example, UK-based software company KeyPoint Technologies has a myriad of keyboard apps for Android, under the Adaptxt brand.
http://thenextweb.com/apple/2014/06/06/fleksy-swiftkey-swype-apples-third-party-keyboard-support/