Is it normal to not "own" your bitcoins? Are 6% transaction fees normal? I downloaded an app on my phone that lets me exchange bitcoins for the local currency. Next, I downloaded the Electrum wallet on my computer and set up a bitcoin account on it too. Now, I bought some bitcoins (for fiat money) from the app. I transferred all the money from the bitcoin account on the app to the bitcoin account in Electrum.

Bitcoin account on app: 3BSRdfCnQ17NWkvxomUXzpfJg38Vif5GLo
Bitcoin account on Electrum: 1A8B5T3cjh4TFHBfagS5fexPz18LgWyUyJ

Now, when I view this transaction in the block explorer, it shows me that the bitcoins (0.040151 BTC) have been transferred from some other bitcoin account (and not from the 3BSRdfC account) to my Electrum account. Does this mean that the bitcoin I bought was actually in the app company's account and not in the account they created for me? Is this normal? Ethical?

Next, to send bitcoins to another bitcoin address, the app providers charge "Bitcoin network fees" which can be as high as 6%. Are these rates reasonable? I thought that, with bitcoin, we were supposed to have "lower transaction fees". 6% is exorbitantly high, I think.
There are both custodial and non-custodial online services as well as apps. If it's important to you to control your own funds, you should research the account model your service provider uses and avoid services that manage your funds for you.

Bitcoin transactions are not paid respective to the amount that is being transferred, but rather in regards to the blockchain space that you purchase in order to have your transaction confirmed. Transaction fees have been much higher in the past months than previously, as the supply is capped and demand has been increasing. Personally, I'm hoping that a protocol upgrade by the name of Segregated Witness will be activated soon, as this will increase the blockspace as well as provide access to a payment layer that I expect to work as a valve to curb demand.

For you personally this means that fees are more or less the same size for whatever amount of money you transfer. If you make large payments, the fees will be minuscule, if you make small payments, the fees will be a significant port of the transferred value. Naturally, this is making Bitcoin unattractive for smaller payments.