We are a team of 4 computer engineers, so we should be able to meet the deadline within 20 days.
We are looking forward to have more details about your established configuration and whether you already have an existing database.
If not, we would construct a MySQL database and create the necessary tables and views.
If native mobile apps is not a must, the mobile app will be cross-platform.
We will work on a linux server if none is available.
Additionally, we can create a java web application based on JPA,EJB and JSF with the primefaces framework.
If the mobile app is your only requirement, we can deploy it on a tomcat server. If you are keen with the web application idea, the deployment will be on a glassfish server.
Please note that we offered the lowest bid since we already have worked on a very similar project and it should not be a problem for us.
Our bid doesn't include any web hosting costs, domain prices or server purchase (if not present).
Looking forward to working with you.