MBaaS stands for "mobile backend as a service" and is a model that specifically addresses the cloud-computing requirements of web and mobile app developers by providing a unified way of connecting their apps to cloud services.
Mobile and web apps often use a similar features on the backend, including analytics, push notifications, user management, and cloud storage (among others). These services have their own API that must be individually incorporated into an app and some services require the developer to roll a custom back-end solution. This is often time-consuming and complicated.
MBaaS serves as a bridge between the frontend of an application and various cloud-based backends via a unified API and SDK providing a consistent way to manage back-end data. Developers won't have to redevelop their own backend for each of the services that their apps need to access (saving time/money).
Moreover MBaaS provides scalability, availability and security making the developer's life easier when apps become more popular.
For more info please see http://en.wikipedia.org/wiki/Backend_as_a_service
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