I've discussed this at length elsewhere, so here's my abridged opinion. The main issue is that a "mainstream" personal finance app must have the following two

I've discussed this at length elsewhere, so here's my abridged opinion. The main issue is that a "mainstream" personal finance app must have the following two features: - Automatic download of financial transactions - Intelligent categorization from "STBCKS3134" to "Starbucks [Dining]" Any tool that doesn't have those two features is doomed to be "niche"... used only by people who actually enjoy and/or are disciplined enough to enter their own data regularly. In short, we need a "Twilio for personal finance" so that people can build creative solutions and not have to reinvent the wheel. There are startups out there that are trying to solve this.