Cities aren’t just a collection of buildings, they’re home to billions of people. They are where we expect to interact with one another and work collaboratively to make our communities better places to live. Different technologies—including mobile phone apps—are enabling strangers to connect with each other in their neighborhoods for this purpose. They are empowering individuals to share knowledge, goods, and services—creating real human interaction in economic exchanges that used to be faceless. While there are many apps on the market that facilitate a sharing culture or sharing economy, here are three of our favorite apps that are helping build stronger communities in cities worldwide.

Carma Carpooling

Carma is a platform designed to help users find people nearby who are interested in sharing a ride. Unlike Uber, Lyft, or Sidecar, Carma seeks to connect passengers in a way that allows them to share the costs of driving. At the end of a trip, passengers simply reimburse drivers for the cost of gas and maintenance. The app provides an alternative to traditional mobility options without adding more cars to our roads, allowing people to get around in cities more efficiently and at a lower cost. By facilitating ride sharing, Carma also helps reduce greenhouse gas emissions and wasted space dedicated to parking.

Meal Sharing

Meal Sharing gives people the opportunity to enjoy food and get together with others from their neighborhood they would not meet otherwise. The host can decide how much guests should chip in to cover costs, or whether to offer the meal for free. The app allows people to make new friends in their neighborhood and to build communities through the tried and tested method of sharing food. To ensure safety, users’ profiles are connected to their Facebook account, and users can view others’ past meal sharing experiences before joining. By providing food to your neighbors that would have otherwise gone to waste, the app is also a creative solution to help cut food waste in our cities.

Peerby

Why buy a power drill when you can borrow it for free? By using Peerby, people can borrow almost anything they might need from their neighbors, including power drills, vacuum cleaners, ladders, and many other tools for household projects. Peerby encourages a culture of collaborative consumption—instead of buying a power drill that you will probably use once in five years, you can borrow one from your neighbors. Next time, you can return the favor by lending a push broom to another user. The app aims to establish an alternative consumption culture that reduces the number of wasted items, saves consumers money, and connects needs with people who can meet them.

Better Technology for Stronger Communities

Improvements to mobile technology are creating a level of connectivity that allows strangers to share with one another. Apps like Carma, Meal Sharing, and Peerby use the power of this mobile technology to build trust among complete strangers. On all three platforms, users on both sides of a transaction can rate their experience. This feature improves safety and can make your personal reputation a valuable asset online. These apps are facilitating not just transactions, but also community connections that are built on personal relationships rather than anonymous transactions.

Access to smart phones and the Internet makes it possible for information to be shared within seconds, fostering all kinds of innovative economic activities, encourage new forms of collaborative consumption, and lowering the costs to our wallet and the environment. These technologies will help cities become sustainable and connected communities for people.