代わり

にかわって shows a replacement of a normal something with something else - where the thing being replaced is what's normally used/present. It cannot be used for something that's changed on the fly. You can use it to say if someone is replacing someone else who is ill/unavailable, or showing change over time (from tapes to CDs, gas-based cars to hybrids), etc.

のかわりに/かわりに shows a balance between the thing replaced and the thing being replaced. In exchange for one, the other is used. This goes well with nouns. It's even clearer with verbs: you say that since you're not doing something, you do something else instead.