Q: iOS iPad

You can not download Apps, because you do not have a WiFi connection.

IF, and this is just a random guess, you have plenty of storage for Apps, however you can NOT download Apps without a WiFi connection.

Also, as has been stated repeatedly, you can not upgrade the storage capacity.

What message do you get, if any, when trying to download something?

Can you please post the exact wording of the message?

Ah, thank you, now I understand the issue. This means that your iPad is running on an outdated operating system. You can open the Settings app, tap on "General," and then tap on "Software Update" to check for available updates. If you download and install the update (which is iOS 9.3.5 right now), then you should be able to download Skype after that.

Sorry, you are making this unnecessarily complicated. You reply with a different error message each time. Please check Settings - General - About - Model = ??? Version = ???

Do not reply with unrelated answers.

Can you find some location that offers Wi-Fi - an Apple Store, perhaps - and download the update there? Really, I would not be relying on a cellular connection through Verizon as my only means of connecting to the Internet. It might be worth investing in your own Wi-Fi router.

As to the second part of your post, I am not sure that I understand. It sounds like you have two concerns: that your iPad needs iOS 8.4.1, and that you only have 3.6GB of storage left. For the first concern, note that you can only update to the latest version of iOS (which is currently 9.3.5) compatible with your iPad, and updating to intermediate versions is neither necessary or possible. As for the lack of storage space, the only way to gain more storage is to delete content that you no longer need which is currently taking up space. Try deleting photos and videos that you no longer need.

Yes, that is quite a predicament. At this point, your only options would be the ones I outlined earlier, which would be to find a location with Wi-Fi (i.e. Starbucks, Apple Store, a public library) and download the update there, or to invest in a Wi-Fi router of your own.

First, it is not called "wireless Internet." What you have is a cellular connection. Using the correct terminology may help clear up some of the confusion. Now, your iPad is capable of both Wi-Fi and cellular connections. You have a cellular connection through Verizon. In order to download the iOS update, you need a Wi-Fi connection.

You need to physically travel to some location like the ones I mentioned earlier that offers Wi-Fi, and connect to that network. Once there, all you need to do is open the Settings app, go to the Wi-Fi menu, and look for available networks. Tap on one that does not have a lock symbol to join it. Then you will be able to download the iOS update.