You can change the default transaction fees in the settings. Keep in mind that they are not the ones taking the fees but it's a fact that right now the higher fees are being processed quicker by the miners — you can do a small fee and get stuck for 3 days (it has happened to me) so I just use a higher fee and have funds confirm quicker.
In terms of it being unstable, I've found that if you are not on a stable network (3G, 4G, wifi etc) it can be sluggish.
But overall I like it a lot.
Thank you for this. I'm yet to make my first transaction and want everything to be right. Candles, rose petals on the pillow, reliable wallet etc.
Hahaha I hope you have a good first time.