Wikipedia:Version 1.6 of Android added support for speech synthesis (TTS).
But my question is "Does any Android device has TtsService.apk"?
Android 1.6+ has a built-in TTS service on every device (short of, maybe, some extreme customizations). For extended TTS services - i. e. the ability to use plug-in third party engines - one has to download the free "TTS Services Extended" app from the Market.
On Android 2.2 and above - the majority of the current installed base - the extended TTS service is baked in.
The specific APK name is irrelevant, it's an implementation detail.
EDIT: 1 . Quoting http://developer.android.com/resources/articles/tts.html :
Starting with Android 1.6 (API Level 4), the Android platform includes a new Text-to-Speech (TTS) capability.
2 . What do you mean by "TTS (files)"? The standard engine on Android 1.5 and below? The extended TTS service? Some third party engine? Your own engine?