There are quite a few free IPTV services but most offer low resolution or very limited number of channels. Even most offer only on-demand content (pre-recorded movies or shows). To actually watch live TV broadcasts you need, there is a provider for this, but I think the best service is FUJITV (fujitv.live). The do charge a modest amount for their service but it is the best IPTV service currently available. They offer over 70 channels including virtually all the cable channels you might want, like Theatre, Film, Children's programmes, TV series, Entertainment programmes, Teleshopping and comprehensive news coverage, etc. Also has a wealth of sports, like Sumo, Japan professional baseball and the Japan Professional Soccer League, etc.
Fujitv Live is a very simple and fast Japan TV Live streaming, you can download the apk on your any Android-based devices: http://fujitv.live/download/fujitv.apk
More Important is that now FUJITV Live is Free!!! Ended in June, 2017. However, if you order it during this period, you can get 20% discount: http://fujitv.live/subscriptions
FUJITV Live is a very inexpensive service compared to other live software. Worth experimenting with its free version!
Now watch your favorite Japan TV shows live for free through FUJITV Live: http://fujitv.live/fujitv