App Development Job

Hi! Our company is looking to create a new "Shopping-List App" for Android & Apple. However, we want it developed as a standard "HTML5 Web-App" which is then packaged-up for Android & Apple devices using the "PhoneGap" service, (unless you recommend something better), to keep cross-platform development & maintenance costs as low as possible. Obviously the general requirements for this App are self-explanatory (and obviously many other Shopping Apps already exist), so we would provide more specific details about our App's layout later, but before that, we'd like to know about the feasibility of some other "specific" functionality that we would like included: Basically - we really want to try and avoid the need for any servers "behind the scenes", to manage, process, store & share data, as well as for sending & receiving alerts & messages etc.... ** We really want all of this to be managed & processed "directly between phones" ** Like this, "scalability" will not be a problem for us. The functionaility that we are looking for - without the need for any servers – is as follows: - One device would act as the "master device" in each Group (a "Group" = a "household") - Additional devices would input the "user_group_id" and "password" found in the settings of the master device, to become a member of that group, i.e. to share Shopping Lists... (or perhaps joining a group could be done semi-automatically for other devices on the same Wi-Fi network that have the App installed?) - Devices must have "multi-way" syncing, so "any" user can update lists, and "all" devices in the group are updated (not only via WiFi, but over data connection too) - A simple "Group messaging" facility is required within the App (sends to all users in the "Group") - App "Alerts" are also required - we also want the facility for "us" to send our "own" alerts out to every phone who has downloaded & installed our App on their phone... So can this type of functionality be achieved, without the need for a dedicated server(s)? WHAT WE ARE LOOKING FOR IN A DEVELOPER / COMPANY : Ultimately, we are interested in building a mutually beneficial, "long-term" relationship with the right developer / company. i.e. as we want to add new features and expand our product, we would look to this partner not only for their App development skills, but also for their ongoing technical support in scaling up the business in the future. We look forward to hearing from you. Thanks! Simon