MobiMatter

MobiMatter operates as a global eSIM marketplace, connecting travelers with plans from multiple providers including IIJ's Japan network. Pricing starts as low as $0.3 per gigabyte, making it one of the cheapest options for data-heavy visitors. The service supports hotspot tethering, so you can share your connection with travel companions or other devices without restrictions.

This marketplace works well if you're comfortable comparing multiple plan options and don't mind using a third-party aggregator. The IIJ infrastructure typically delivers solid coverage across urban and suburban Japan, and the low per-GB cost appeals to travelers who want flexibility in how much data they purchase upfront.