Interesting. I did previously search Lazada for "Parabolic Microphone" but this Rode was the nearest thing they showed. I had also thought about using something smaller, maybe teacup sized, around just the mic, so the whole unit would attach to the phone. I got no further than an idea. Perhaps a very lightweight disposable food bowl would work? It would need to be somewhat parabolic in shape, light in weight and in a workable material.
I hadn't thought of plant pots. Good idea.
To be fair, I think the failings are in the app rather than in the hardware. I can probably go outside now and get a tree sparrow, a tailorbird and a purple sunbird, the app seems to identify them easily. Plus the ever-present chickens. Other birds it gets with difficulty even when they are singing clearly, that magpie robin for example, the app identifies it only occasionally. This is not a complaint, the app is a massive undertaking with over a thousand Asian birds in its database. It could become brilliant over time. I can hear maybe half a dozen different birds calling right now but if I step outside I'll probably see only one or two without binoculars, so a good sound ID would be really useful.