Sorry, I found similar questions - but not the answers: only discussions. I'm developing android application which is intended to place points and draw routes on map. In case Google limits using of their maps 2500 r/day per key - there is no way to use it, since even in case your application was once sold - you'll need to pay every month for every additional 1000 req/day. Especially it is unclear for free application: how much it will cost for 100000 downloads per month after 1 year? Please, share your experience (not your assumptions). Thanks.
use of the Google Places API for Android request based on Application key based.
After 150000 request per day whoever using your application "that means the "key"
which you given for google places api request" will get a response error
from google api as "USAGE_LIMIT_EXCEEDED" like
while giving search text in search view(to check the response debug and see
the Exception occurs while sending request to place api) , but it wont't be
visible to the user who uses you app. It will simply shows no
movement in markers and no auto suggestion will come. For that you want to use
for unlimited request. but it contains lots of restrictions by google. They
will track your app closely. If any violations of google policy happens means
you app will get banned from GooglePlay Markert. so make sure in that you
app does't contains any violation policy before using this.
It is not entirely clear which limit you are looking for because the "usage of maps" can follow into a number of different map API categories. For just displaying maps, you can display unlimited maps without usage limits on moblie apps using the Google Maps Android API v2 -- the supporting documentation comes from the FAQ.
The Maps API usage limits apply only to the following Maps API services:
Google Maps JavaScript API v2 Google Maps JavaScript API v3 Google Maps API for Flash Google Maps Image APIs: Google Static Maps API Google Street View Image API
Note that Google Maps Android API v2 does not appear on the list, and thus, is not subject to usage limits.
However, your question seems to be asking about routing, not maps. If you need routes, you need to use the Google Directions API, which is not part of Google Maps Android API v2, and subject to its own usage limits. Specifically, 2500 requests per key per day. Since directions is not tied to mobile app, it has no notion of a device.
In summary, if you want to display a map with a route you have generated on your own, there are no limits. If you need Google to give you the route, you can only do 2500 requests for routes per day. If you need more, you have to get a Google Maps API for Business account or find another routing solution.
From FAQ google maps API: "The Google Earth API, and native Maps APIs for mobile platforms such as Android and iOS are not affected. Use of the embed feature of Google Maps, and other Google products that offer an embed feature that includes a map, are not affected by these limits."
Google has shared the API licensing structure. See link below. https://developers.google.com/maps/faq#usage_pricing
来源：https://stackoverflow.com/questions/14697180/google-maps-api-for-android-limit-2500-requests-day-is-per-client-device-or-per