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Is a WCF Web Service an API?

I am working on a Visual Studio Application that references a WCF web service, and after some reading online I am pretty confused.
I have read that WCF is a framework for building a web service, but it is not an API. Is this true?
I was under the impression that Web Services are APIs; I always thought that APIs were Software as a Service (SaaS). Doesn't that mean that APIs and Web Services are pretty much the same thing? Or do I have the wrong idea?
Could this be a misconception of my understandings of SOAP and REST?
Basically I want to know whether a WCF built web service counts as an API, and why/why not?

WCF is an API that can be used to create APIS within your application.
Web Services usually involves creating an API within your application. There are valid APIs that are not Web Services, like the Win32 API.
Its possible to build a WCF web service with one web method for an application that would not be considered an API specifically since it does not contain a set of routines, protocols, or tools for building applications.
Review http://en.wikipedia.org/wiki/Application_programming_interface for what an API is.

According to wikipedia, yes, yes it is:
APIs often come in the form of a library that includes specifications
for routines, data structures, object classes, and variables. In other
cases, notably SOAP and REST services, an API is simply a
specification of remote calls exposed to the API consumers.

An API (Application Program Interface) is a way to interact with components of a system. It defines the operations that can be used to get data out or push it in.
WCF (Windows Communication Foundation) itself is a framework for building web services and other applications that need a communication channel to share data with other services/applications, it is actually a lot larger on what it can do. You can read more about it on MSDN. It is an API as it gives you objects that allow you to tell it interact with its' components.
REST and SOAP are just architecture styles that can be used to serve data via a service, it is defining how you should interact with the data rather than the components themselves.

What tools/methods are used to consume WCF web services for Android?

I am designing an Android application which is supposed to connect to a server via WCF web service.
I have a WCF web service written in .NET 4.5 and it is a self-hosted web service. It has SOAP endpoint configuration and it is not a very complex service, however it does include some methods which return DTOs (Classes containing lists, other DTOs and value types).
Now the problem I am facing is that I wish to use some sort of tools to consume the web service definition and generate the proxy classes. I have been successful doing this with the help of Eclipse, but the resulting generated code uses alot of external libraries not available within Android.
Now my question is, what are the preferred tools/methods to consume WCF SOAP web services?

I found that using the following tool gave me the best generated code.
https://code.google.com/p/android-ws-client/
I do recommend this tool to anyone looking for consuming a WCF SOAP web service.

What's the difference between WCF Web API and ASP.NET Web API

I've done a bit of work in the past using WCF WebAPI and really liked a lot of its features, I'm just playing with ASP.NET Web API at the moment and it seems completely different (IE completely removed from WCF).
Does anyone know which features of WCF WebAPI are included in ASP.NET 4 Web API?

Ive done a little more reading around this and found a few pages by MS people on this:
http://wcf.codeplex.com/wikipage?title=How%20to%20Migrate%20from%20WCF%20Web%20API%20to%20ASP.NET%20Web%20API :
The WCF Web API abstractions map to ASP.NET Web API roughly as follows
WCF Web API -> ASP.NET Web API
Service -> Web API controller
Operation -> Action
Service contract -> Not applicable
Endpoint -> Not applicable
URI templates -> ASP.NET Routing
Message handlers -> Same
Formatters -> Same
Operation handlers -> Filters, model binders
and http://wcf.codeplex.com/discussions/319671
The integrated stack supports the following features:
Modern HTTP programming model
Full support for ASP.NET Routing
Content negotiation and custom formatters
Model binding and validation
Filters
Query composition
Easy to unit test
Improved Inversion of Control (IoC) via DependencyResolver
Code-based configuration
Self-host

From what I've learned, Microsoft did a little bit of naming confusion here.
I'm assuming you know what WCF is all about, this big framework built on top of XML to allow user to build distributed services with a wide variety of technologies (from SOAP to REST to MSMQ etc.).
It's hard as hell to use (for me at least) and requires a lot of bootstrap to have it working, and eventually they realized this and started providing some default configuration for simple http services (WCF REST starter kit anyone?). ASP.NET MVC was gaining momentum and some of the features it provided (automatic arguments matching for example) started to show up in WCF.
Now that's the situation:
Announcement: WCF Web API is now ASP.NET Web API! ASP.NET Web API
released with ASP.NET MVC 4 Beta. The WCF Web API and WCF support for
jQuery content on this site wll removed by the end of 2012.
http://wcf.codeplex.com/wikipage?title=Getting%20started:%20Building%20a%20simple%20web%20api
And that's better imho.
I'm quite sure it should be possible to host asp.net mvc4 webapi on top of WCF (if you ever need that), but i can't find documentation that can prove me right (or wrong).
UPDATE (can't fit as comment):
Wait, there is a huge different between "moving a subset of communication technology from a library/framework to another" and "replace WCF". I personally think that WCF was designed for some kind of communication concept and it has a rather cool design, but the distributed computing is somewhat moving on to new (and simpler) solutions (look the feature-rich SOAP vs the lean e flexible REST, although many people still use REST in a RPC manner), and i think that this kind of programming patterns better fit into the MVC architecture than the WCF one. Effort was put on designing some simple way of building/consuming web services on top of WCF, but they eventually found out that it was not the right solution.
Not to mention that many developers now use ASP.NET MVC and want to do rest web services for their web app, messing with WCF is often overkill for these kind of things, and I've experienced that on my own skin.
I think that the routing mechanism is awesome and the right way to go, and if you look closely, they included part of it (with different names and types, but the pattern was there) in WCF. So yeah, i think that if MS don't dismiss that part of WCF WE should do it. To strictly answer, no, i don't think you'll ever find WebGet/WebInvoke in asp.net mvc*, it just don't fit in.
Yeah self-host is probably the only bit of WCF contained in ASP.NET MVC4 right now.

It looks like WCF itself is somehow dying or at least becoming much less important then it was supposed to be and because of that it also has much less development effort put into its feature set. New features in WCF itself are more cosmetic.
WCF was designed as transport / protocol independent way for inter process communication. Even the idea was independent abstraction it was mostly build on top of SOAP stack. When WCF 3.5 brought support for REST it was mostly hacked in because REST is all about transport dependency. Using transport independent API to support inter process communication which is done through directly using transport features appeared inconvenient. As result MS first released WCF Rest API Starter Kit which never reached RTM but it was preview of features which was later included in WCF 4 and finally in .NET 4.5 or WCF Web API. Because REST is transport dependent and currently used only with HTTP (even it is theoretically possible to use other transport protocol) the API was moved to .NET part which is more suitable for HTTP processing - to currently very popular ASP.NET MVC.

WCF Web API is replaced by ASP.NET Web API which takes features from WCF Web API and merges them with the features from ASPNet MVC. ASP.NET Web API is a new (02/2012) framework for building and consuming HTTP services and a platform for building RESTful service.
Although not in the original question it seems worth noting that WCF is alive and well and its REST support remains useful when you have existing SOAP (WS-*) services you must support but want to add REST to reach more clients.
Reference
CodePlex: WCF Web API is now ASP.NET Web API
CodePlex: Daniel Roth on the Future of WCF
Chanel9: Dan Roth on the new ASP.NET Web API

The following excerpt found on this MSDN page summarizes this dilemma well.
Use WCF to create reliable, secure web services that accessible over a variety of transports. Use ASP.NET Web API to create HTTP-based services that are accessible from a wide variety of clients. Use ASP.NET Web API if you are creating and designing new REST-style services. Although WCF provides some support for writing REST-style services, the support for REST in ASP.NET Web API is more complete and all future REST feature improvements will be made in ASP.NET Web API. If you have an existing WCF service and you want to expose additional REST endpoints, use WCF and the WebHttpBinding.

Here is good article on Web Service, WCF and Web API http://goo.gl/T29A5B
Web Service
Based on SOAP and return XML Data
Support only HTTP protocol. It support only HTTP protocol.
Consumed by client that able to understand xml SOAP Services.
Can host on IIS. It can be hosted only on IIS.
Easy to Learn and understand.
WCF
Based on SOAP and return XML Data. SOAP is heavy compare then JSON and its overhead over network also.
Enhanced version of web services support multiple protocols like TCP, HTTP, HTTPS, Named Pipes, MSMQ via configuration.
More reliable when both client and server have .Net.
Its implementation and configuration is complex
Consumed by client that able to understand xml SOAP Services.
Self-hosting, IIS and using windows services.
Web API (Web API 2.0)
Design specifically for building HTTP Restful Services on .Net Framework.
Web API easily readable and handy as JSON.
Support all features of HTTP Like URls, Request/Response, Headers, Caching and Versioning.
Web API support many HTTP Verbs like GET, POST, PUT, DELETE etc.
Web API is stateless.
Web API supports MVC features (controllers, action results, routing, filter, model binders, IOC container or dependency injection)
Web API can be self-hosted, hosted with in the application and on IIS.
OWIN (Open Web Interface for .NET) is used for self-Hosting.

ASP.net web api is lightweight and REST support inbuilt. It is more suitable for mobile applications.WCF is bloated with more options . It depends on the complexity of the system to select one of these.

Web service written in both WCF and Java

Can I write a web service that implements the same methods and returns the same custom objects using both C#/WCF and also Java Web Services? And if so, can I then access the web services using a single web reference but with different addresses?
I'm asking because I have to host a web service that has a GetCitations and GetTerms method for publically exposing our database content. We are on IIS, so I was going to do it with WCF. However, other partners in the project also have to host an equivalent service and they are all Java based.
We are then building a software app that needs to connect to any number of these services (as defined at runtime by a user). I am expecting that we can have one set of classes to connect to these services (but with different endpoitn addresses), but am not sure whether I'm right in expecting this to work.
Is this possible?
And what considerations/restrictions are there?
Thanks.

It shouldn't be a problem, if you make sure that both services have equivalent wsdl files and you use http/soap binding.
I am not sure about using the binary (net.tcp) one with WCF, though. It might be a problem.

One way to do it is to use JAX-WS (Java 6) to expose a method as a web service.
The JAX-WS stack allows for automatically generating the correct WSDL at runtime.
The .NET team can then take that WSDL, and use standard tools to create a mock implementation of that WSDL. This mock implementation is then used as the actual .NET implementation, and you then use standard tools to generate the WSDL for that web service.
You now have to web services with the same semantics each with their own WSDL.

Both Java and .NET can implement a SOAP compliant web service, so the answer is yes, you can write a .NET and a Java webservice that implement the same WSDL.

Microsoft Client - Java Web Service

I have to consume a Java web service and want to do it using Microsoft Visual Web Developer in C#. I will be adding the endpoint of the web service as the web reference and hopefully go from there, however I am concerened if there will be any interoperability issues? Any help would be appreciated.

There won't be any interoperability issues if the Java web service respects the standards.

You should be able to generate a client from the WSDL and XSD that describe the service. This ought to be fairly routine.