Help thinking through playing my bass through my phone over bluetooth

My first floor of my house will have regular speakers hooked up to an A/V receiver. I can play music through spotify over my phone and send the music to bluetooth in the receiver. What I would like to do is plug my bass into my phone's microphone input and adjust the input level so that I can play along with the music and have my bass go through the speakers as well. I know there might be some latency issues etc... but does anyone have a good solution for this? Would iRig Mobile or something similar work for this?

This isn't my main practice space so I'm just looking for something that is super quick/convenient to plug into because I keep a bass on the first floor but not a amp/cabinet. Any ideas how to accomplish this? Or is this just a bad idea to begin with?

 

Thanks, I think you're right. I'm thinking that it's going to be too much trouble and I should just pony up the money to purchase a small amp as you suggested.