We have customized a few existing tools to suit our testing and production. Maybe they will also be useful for you as well.

Online font testers: Web-based font testers to proof your fonts:
Latin, Devanagari, Hebrew (Beta)
(Based on Pablo Impallari’s tool)(currently offline)

Indic Type Cooker: Get recipes for inspiration for Indic type sketching.
(Based on the original Type Cooker)

Devanagari Type Design Resource Listing: Our list of recommended books, websites, and tools useful for Devanagari type design.

Lists of words useful for testing type: Random and fun, we’ve made these collections over the years to be used to evaluate your type.