Your intention to retain the application in GAE and use AWS to perform a few tasks, that can not be performed in the GAE, seems for me a right scenario.
I'd like to share a few ideas along with some resources to answer the main part of your question:
Is there a simple way to pass specific tasks from gae to AWS? E.g. A task queue?
If you need GAE and AWS to perform the task all the time (24/7) then your application will definitely depend on batch schedule or task queue. They are available by GAE.
However if you could arrange to pull the task in GAE and perform by AWG on interval basis (say twice a day of less than an hour each), you may no need to use them as long you can manage the GAE to put the data on Google Cloud Storage (GCS) as public.
For this scenario, you need to setup AWS EC2 Instance for On/Off Schedule and let the instance to run a boot script using cloud-init to collect the data through your domain that pointed to GCS (c.storage.googleapis.com) like so:
wget -q --read-timeout=0.0 --waitretry=5 --tries=400 \\
--background http://your.domain.com/yourfile?q=XXX...
By having the data from GCS, then AWS can perform these specific tasks. Let it fire up GAE to clean the data and put the result back to GCS to be ready to be used as your mobile application back end.
Following are some options to consider:
- You should note that not all of the EC2 types are suitable for On/Off Schedule. I recommend to use EC2-VPC/EBS if you want to setup AWS EC2 Instance for On/Off Schedule
- You may no need to setup EC2 if you can set AWS Lambda to perform the task without EC2. The cost is cheaper, a task running twice a day for typically less than 3 seconds with memory consumption up to 128MB typically costs less than $0.0004 USD/month
- As outcome of rearranging you your application in GAE and set AWG to perform some of the tasks, it might finally rise your billing rates, try to to optimize the instance class in GAE.