I've searched for this several times and haven't been able to find an apk download anywhere. This is the developer's website...

http://www.johospace.co.jp/

...unfortunately, I don't speak/read Japanese. If there is anyone on the forum who does, would it be possible for you to leave a message at his website to let him know there are a number of EE people who would like to get the apk (English version), explaining that we are not able to download from the market place?