I don't know how much the installed size of the app is. But considering how the install process works, the explanation might be easy:
- the
.apk
is downloaded to /data/local
(internal storage)
- for installation, it might require some unpacking, with temporary files again being created on internal storage
- only after that, the app will be stored to its final location (in your case, Link2SD would then take care to move things to your card)
Checking with our insufficient-memory tag-wiki, you will find that the "insufficient memory" error is triggered when available free space on internal storage falls below ~ 25 MB. Now let's make a little math: You've got ~64 MB free there. The .apk
is ~18 MB. We need to leave ~25 MB to not trigger the error. So: 64 - 18 - 25 = 21. If the installation process requires more than 21 MB for temporary files, you've got your explanation. With the (packed) .apk
file already being 18+ MB in size, it's very likely to break that limit.
For a possible work-around, you might want to take a look at Configure Play Store to download temporary files to SD Card.