BublMe

Bublme is a social networking system based on the anonymity and real interactions of its user base. It consists of a platform which facilitates and encourages physical meetings between users, and also offers a user rating system.

Each user creates a profile. The profile will consist of two parts: private data and public profile. The private data, which can identify the user directly (e.g. name, email, location, etc.), will never be accessible to other users of the system. The public profile will be available to all the users who can interact with its owner, and will only consist of generic data pertaining to gender, age, looks, life situation, without getting specific enough so that it may help identifying the user directly. Although every profile will have an associated nickname, Bublme does not enforce unique nicknames, and we do not advise the users to follow others by their nicknames.
After completing the profile, every user of the system can create "bubbles", which are invitations addressed to other users to meet and take part in specific activities, announced therein. Every bubble will have a time, a place, a description, and a duration. Additionally, every bubble can be targeted to a specific audience - for example, people aged 22 - 28, with 70 percent positive ratings, located within 10 km of the user's current location. The match of the target audience is made based on the information available in their public profiles.
By asking to join a bubble, the users are announcing their availability for taking part in the activity that it represents. If their join request is approved by the bubble owner, then they will have to get to the meeting place, at the specified time, and take part in the actual activity. Bublme provides a system for confirming the meetings, and the participants will have to use that system in order to state their presence at the place and time of any meeting. By not arriving at a meeting, the users subject themselves to automatic negative ratings.
After a meeting is confirmed, all participants are required to rate their peers. The meeting creator (or bubble owner) will be required to rate every participant, and the participants will be required to rate the bubble owner.
The ratings are a very important part of Bublme, because they can represent very accurately both the frequency with which users take part in actual meetings, as well as the quality of meeting that can be expected by accepting to meet them. Therefore, after a meeting is confirmed, the system will not allow creating or joining another bubble until the user rates the bubble owner (or the participants).

Upon asking to join a bubble, the users can view each other's profiles, and also chat, and exchange photos. The meeting does not become mandatory until the bubble owner accepts a user's join request.
The system does not provide any means to create a list of contacts, or to interact with the users from past bubbles. The only way to interact again with a user within Bublme is to join one of their new bubbles. The users are free to exchange contact details outside the system, however they are irrelevant and cannot be used inside Bublme.

TL;DR - You get to meet real people. You are completely anonymous. You don't have a list of contacts. You can set the criteria for whom can see your bubbles and ask to meet you. You only see the bubbles where you are a match for their set of criteria. You can chat and exchange photos with the users prior to meeting them, but only after requesting to join their bubbles (or after they request to join yours). You can only join bubbles and take part in meetings if their owners approve your requests. You give and receive ratings after meetings. People will see your ratings and judge you by them. Be honest with your ratings. Have fun and stay safe!