AGPL-3.0
The GNU Affero General Public License, version 3 (AGPL-3.0), is a copyleft open-source license. Like the GPL, it lets anyone use, modify, and share the software as long as they pass on the same rights. It adds one condition: if you modify the program and users interact with it over a network, you must offer them its source code.
How it works
Section 13 of the license is the difference from the GPL: a modified version that users reach through a computer network must prominently offer those users the corresponding source, from a network server at no charge. The GPL only requires source when you distribute copies.
Everything else follows the GPL-3.0 model: a program that includes AGPL code and is conveyed to others is licensed under the AGPL as a whole, its recipients can get the source, and no further restrictions may be placed on their rights.
Why it matters
The AGPL keeps hosted services from using open-source code without sharing their changes, which is why many open-core companies publish under it and sell a commercial license to teams that cannot meet its terms.
App stores are a common sticking point. The Free Software Foundation has said that Apple's App Store usage rules add restrictions the GPL forbids, and the AGPL carries the same rule against further restrictions, so closed or store-distributed apps usually need a different license.
How it relates to Offline Protocol
The Offline Protocol mesh SDK is published under AGPL-3.0-only. It is free to use in production, including for a business, when you meet the AGPL obligations, such as offering your users the corresponding source.
Proprietary apps, closed-source firmware, and apps distributed through the Apple App Store need the commercial license instead, which is annual with no published price. The OfflineID and Proof of Location client packages are MIT or ISC, and the CLI is Apache-2.0. See pricing.
Frequently asked questions
What is the difference between the GPL and the AGPL?
Both are copyleft licenses. The AGPL adds section 13: if you modify the program and users interact with it over a network, you must offer them the source of your version. The GPL only requires source when you distribute copies.
Can I use an AGPL library in a commercial app?
Yes, if the app meets the AGPL: it is licensed under the AGPL and its users can get the corresponding source. A proprietary app, or one distributed through an app store whose terms conflict with the license, needs a commercial license from the copyright holder.
Is the Offline Protocol SDK free?
The mesh SDK is free under AGPL-3.0-only, including in production, and local mesh traffic is never metered. Closed-source and App Store apps need the commercial license; contact us for pricing.
