I switched to Ahamo from SoftBank in May. Done it online. No need to go to offline shop. Smooth process. It is a sub-carrier under Docomo.
Check coverage area before you apply
¥2970 per month you get:
- 20GB (after that limits to 1Mbps, can top-up ¥500 per 1GB)
- 5 minute call free (¥22 per 30 seconds)
- Free 20GB International Roaming for 2 weeks
- Free tethering 0
- Free 20GB International Roaming for 2 weeks
- SMS, phone call
- From Japan to Overseas (phone call, SMS)