What is the best alternative to Mic to Speaker - Virtual Mic on iPhone?

Microphone Live, A tier, #2 in microphone to speaker.

Is there a free alternative to Mic to Speaker - Virtual Mic?

Yes: Microphone Live (A tier, #2) is free to download, with in-app purchases.

No. Mic to Speaker - Virtual Mic is #1 in microphone to speaker.

Mic to Speaker - Virtual Mic is S tier, #1 of 6 in microphone to speaker. Here is everything that competes with it on iPhone, in tier order.

2
Microphone LiveA
Free + IAP · ★ 4.4 · 5,160 ratings · score 83
Turns an iPhone or iPad into a live microphone with low-latency audio, sound controls, and wireless audio output.
3
S1 & S2 Speaker ControllerA
Free + IAP · ★ 4.4 · 12,317 ratings · score 81
Streams music from your phone library to a speaker over Wi-Fi or Bluetooth, and broadcasts live microphone input and.
4
Megaphone - Voice AmplifierD
Free + IAP · ★ 4.1 · 4,039 ratings · score 53
Turns an iPhone or iPad into a megaphone that plays your voice through plugged-in or Bluetooth-paired speakers.
5
Live Voice Changer - PrankcallF
Free + IAP · ★ 4.4 · 4,741 ratings · score 45
Changes your voice in real time through the iPhone microphone, with voice presets, reverb effects and a recorder.
6
Megaphone FREE!!F
Free · ★ 2.6 · 4,658 ratings · score 27
Records and amplifies your voice, and lets you send the louder sounds to friends by email.

What is the best alternative to Mic to Speaker - Virtual Mic on iPhone?: Microphone Live, A tier, #2 in microphone to speaker.
Is there a free alternative to Mic to Speaker - Virtual Mic?: Yes: Microphone Live (A tier, #2) is free to download, with in-app purchases.
Does anything rank above Mic to Speaker - Virtual Mic?: No. Mic to Speaker - Virtual Mic is #1 in microphone to speaker.