You would need to host your mash up on an external server something with a domain or externally accessible IP address.
you could then access the mash up through your web browser on your smart phone.
The WIFI note I guess you are connected to your company network. Assuming also you have authenticated onto your network as well and your machine has a static rather than dynamically assigned ip address and a webserver running on it you could replace localhost with your internal ip address and see if that will work.
So basically you need to look at what's involved in deploying your mashup/app to an external environment (think server edition). Let me know I'd be interested as well.
Up till now you'll have been using desktop edition. To allow other users to share your dashboard you need to present it in a shared environment.
One is upload to cloud. this is fine for limited number of users but a couple of issues.
1. Not secure in the sense its publically accessible
2. If you've extended your dashboard through use of extensions they currently don't work on the cloud.
The second is to install server edition on an externally accessible server and upload your app to it where you can assign permissions to access the app. In this case you would need to purchase licences called tokens to cover the expected usage. (types of licences one for another discussion)
Once that's up and running you will be able to create your mash up using server based app. Your mash up needs to be hosted on an external server to. Can be the same or separate webserver as long as they can connect.
When you are on an external site you can then connect to it through which ever device you want.
These are big topics Paul so suggest you chat to Qlik about how best they can support your aims.