Abstract: Implementations described herein relate to filtering content items from a set of eligible content items based on a device filter. A mobile application may be incompatible with one or more devices based on an operating system, an operating system version, hardware configurations of the one or more client devices, etc. To remove incompatible content items, a device filter can be generated by comparing a set of required features for the corresponding mobile application with data from a data structure identifying several known mobile devices and associated sets of features. The set of required features for the mobile application may include a minimum operating system version, one or more eligible countries, and/or one or more features of a mobile device. The device filter can include a set of identifiers for the known mobile devices that are incompatible with the mobile application based on the comparison.

Abstract: An application and system are provided that prevent an application repository from accepting a new installation package if the new application installation package would not be successfully installed on devices to which it is directed. The version number and constraints provided with the new application installation package may be compared to that of installation packages already existing or published within the repository to determine whether or not the new installation package will be unreachable by a device group to which it is directed. An indication may be provided if that new installation package is unreachable by at least one device group to which it is directed.

Abstract: An application and system are provided that prevent an application repository from accepting a new installation package if the new application installation package would not be successfully installed on devices to which it is directed. The version number and constraints provided with the new application installation package may be compared to that of installation packages already existing or published within the repository to determine whether or not the new installation package will be unreachable by a device group to which it is directed. An indication may be provided if that new installation package is unreachable by at least one device group to which it is directed.

Abstract: The subject matter of this specification can be embodied in, among other things, a system that includes a container document, a plurality of portable program modules residing in the container document, and a repeater residing in the container document. In addition, at least one of the plurality of portable program modules may be configured to define a communication channel and to identify itself to the repeater as a publisher to the communication channel. Furthermore, at least one of the plurality of portable program modules may be configured to identify itself as a subscriber to the communications channel.