Whats the best way to place content without using a lot of categories?
There is no definite answer to your question but I think you can get pretty much what you want using just two types of categories.
Section setup

create 2 category groups:

device types (with the deviceTypes)
post types (with the postTypes)


create an Articles section (with the article handle)
configure you section with the following Entry URI format: {articlesDeviceType.slug}/{articlesPostType.slug}/{slug}
on the entry type of the articles section (you just need one entry type), add the following required custom fields:

Device type (with the articlesDeviceType handle)
Post type (with the articlesPostType handle)



Your entries should now have the URL structure you wanted.
Archive page
Now if you want an archive of all smartphone related tips, you can get the entries with the following entry query in a template:
{% set tipsCategoryId = craft.categories().group('postTypes').slug('tips').ids() %}
{% set smartphoneCategoryId = craft.categories().group('deviceTypes').slug('smartphones').ids() %}

{% set entryQuery = craft.entries().section('articles').relatedTo([
    'and', 
    { field: 'articlesPostType', targetElement: tipsCategoryId },
    { field: 'articlesDeviceType', targetElement: smartphoneCategoryId },
])

This should return an EntryQuery matching all entries related to both smartphones device type and tips post type.