It’s that time again: 500 Startups just put on demo day for its ninth batch of companies at Microsoft’s conference building in sunny Mountain View, Calif. The seed stage investor and startup incubator showed off 29 products and services that range from making it easier to get a home loan to a marketplace for 3D printed knick-knacks.

We don’t want to disservice our readers or the startups we saw today by only briefly mentioning what each is doing, so we’re only going to mention the companies that we found to have the most potential. We selected the following companies based on the quality of their early products and the market they’re addressing. In no particular order:

KangaDo

Co-founder and CEO Sara Schaer described KangaDo as the “Uber for after school car pools.” The app is by parents for parents, allowing them to coordinate playdates and rides for their children to and from school and practices.

Parents are organizing into groups based on neighborhood or school. The startup has already partnered with several Bay Area school districts, which will be promoting the app during the back to school season and also monitoring the school’s groups, ensuring only school parents are using the app. Obviously parents will like this app, but kids who used to get stuck waiting for a ride home will love it.

Zootrock

Running a social media account is harder than it looks, and for most small businesses it isn’t worth it to hire a person to manage Twitter and Facebook profiles. Still, engaging with your customers outside of direct transactions can be important for strengthening ties and maintaining mindshare.

Zootrock takes most of the work out of creating and managing a social presence. By feeding its algorithms certain preferred sources and topics, you can give it an idea of what kinds of posts you’d like to see go up on your streams. Once you start approving tweets and posts that it generates, it recognizes what you’re looking for and can be set to post on “autopilot.”

Vessel

While most of us can’t help but yawn at the latest “marketing solution,” Vessel‘s service actually makes it easier to improve the user experience in an app faster than you could with traditional development tools.

Vessel includes all of the analytics tools that developers expect. The real trick to its service is that it lets you act on data coming in from analytics without waiting for updates to make it through App Store approval. By adding a bit of code, it lets product teams adjust an app’s interface and workflow in a WYSIWYG interface that can be pushed out to different groups of users in order to test the effects on engagement and sell-through.

You can’t seriously change functionality of an app from Vessel without deploying an actual update, as Apple wouldn’t like that very much. But by using Vessel’s analytics and editing tools, you can fiddle with workflows in an app to make sure that people are getting to the point where they might by something faster and with less frustration.

GogoCoin

Whether you believe cryptocurrencies are the future of e-commerce, it’s still commonly understood that bitcoin and its ilk aren’t exactly user-friendly. Wallets, the blockchain, verification — for most people, it’s simply much easier to stick with the credit cards or services like PayPal, even with the hassles that come with them.

GogoCoin makes it easier to jump in to using bitcoin by making it as simple to buy as a prepaid debit card at your local market. You pick up a card, pay a 7 percent redemption fee, and you’re good to go with a bitcoin wallet from Blockchain.

Everyone here loved the end of GogoCoin’s presentation. The company pulled an Oprah moment, asking us all to look under our chairs to find one of their prepaid cards.

AbbeyPost

In a marketplace where retailers like Abercrombie & Fitch and Lululemon refuse to make plus sizes, Abbey Post’s founder Cynthia Schames says her company grew out of frustration she personally experienced when searching for fashionable, plus-sized clothes.

As we’ve covered before, Abbey Post allows women to buy clothes made at their custom measurements at retail prices. Everyone can relate to being unable to find the right fit in the styles they like, and Abbey Post solves that problem. We have to give Schames presentation points for coming out in a perfectly fitted royal blue dress to Sir Mix A Lot’s “Baby Got Back.”

Pop Up Archive

With hundreds of millions of hours of video and music out there on the web, it’s not easy to find the exact piece of content you’re looking for. Unlike text, which can be indexed directly, tags have to be generated or made by hand for videos on YouTube or songs on SoundCloud.

Pop Up Archive uses advanced transcription to vastly increase the textual data we have about the content that’s out there. Right now, podcasters can upload an audio file to the service it’ll generate tags and a transcription (and host the audio in a searchable format), but in the future the company envisions its software letting users search for a reference or character in a TV show and instantly jumping to the points where they show up.

Angelcam

Angelcam is launching a series of apps to make the most of existing security cameras. In the company’s cloud-based app store, users will be able purchase apps that include one that anonymizes faces and another that will track traffic patterns. They hope to one day build a platform that can gather video from security cameras and apply them to big data problems. This could have huge applications, from small business security to cities solving infrastructure problems.

Waffle

Waffle‘s app gives you a grid of four squares that you can fill with different pictures and videos. By swiping a square, your friend can then remix the tiles, allowing you to collaborate to make content that evolves over time. In the presentation, the founder showed a video of herself singing the Mario theme song a capella. Friends shot video separately and then remixed her Waffle by adding their voices, creating a single video featuring each person even though they filmed at different times and places. The app still has a few bugs and won’t be rolled out for about four more weeks.

Thinknum

The world of financial modeling is a mystery to those who aren’t analysts themselves. Institutional investors have immediate access to reports from industry experts, while everyone else is stuck with the information that companies are required to release or the analysis of bloggers. It can all feel like the market is rigged in favor of the big guys. Prices move up and down, and most of us have no idea why.

As we’ve discussed previously, Thinknum is hoping to be a “GitHub for finance.” People will be able to share their valuation models, letting those creating them borrow and learn from those looking at the same companies from different perspectives. With its simple visualization tools, Thinknum also gives a window into the minds of the analysts shaping the market’s expectations.

The concept seems to have fans in the investment community: only yesterday, the company announced that it had raised $1 million in seed funding.