Glow nurture

Gwen • I`m 29 years old, pregnant with #3 and dealing with adenomyosis and APS
Why isn't the Glow <a href="https://play.google.com/store/apps/details?id=com.glow.android.nurture">Nurture</a> app compatible with kindle? I've been using Glow on my Kindle and now that I am pregnant I would like to use <a href="https://play.google.com/store/apps/details?id=com.glow.android.nurture">Nurture</a>, but I can't install it :(