The bad news is that about every app out there has its own level of implementation of OpenType features. And accessing there features can be pretty different across apps, so let's dive a few ones from Adobe, Apple or Microsoft.
Adobe (Illustrator, Photoshop, InDesign)
Photoshop CC 2018 and older do not yet show alternate glyphs in the quick selection previews, leaving empty spots. You can notify the Photoshop team about this issue here and help solve this bug by upvoting it ;)
Apple (Pages, Keynote, TextEdit, iBooks Author, etc.)
By default, Apple apps apply kerning but may not display your extra glyph features. But you can precisely apply (or remove) them via the Typography panel:
- Go to Format > Font > Show Fonts or press Command-T. Then click the gear icon (circled) and choose Typography.
- Then, select the text you want to edit (the Typography panel is context sensitive, based on the selected font).
- Depending on the features included in your font, you will ben able to switch each feature individually.
- Also note that you can set the ligatures setting via the Advanced Options in the Format > Font Style panel.
Microsoft (Word, Powerpoint, Excel)
Kerning, ligatures & alternates are supported in more recent versions of MS apps (i.e. alternates work in Word 2011 but may not in Word 2008).
If kerning or ligatures are not visible
- Select your text then right-click and pick Font... (or press Cmd+D)
- Check the Enable all ligatures in document
- In Character Spacing check Kerning for fonts
- Enter a value that is smaller that the current text size
Also, due to bugs in previous version of Fontself Maker (2.3.1 and older) such features could not work as expected. Just open them in Fontself Maker 2.3.2 or newer and Save/Export them again to check.